The Royal Caroline Institute of Stockholm awarded Santiago Ramón y Cajal (1852–1934) the Nobel Prize in Physiology or Medicine on December 10, 1906 in recognition for his incomparable work. His discovery that nerve cell are discrete and individual, and his foundational work on the principles underpinning the neuron doctrine, still govern our understanding of the brain today (Kandel, Reference Kandel and Marengo2007). Regarded as the father of modern neuroscience (Portera-Sánchez, Reference Portera-Sánchez2002; Venkhatesh- Venkataramani, 2010), he is so exceptional that his works are among the most widely cited in the specialized literature, also over the years and relative to other Nobel laureates (Reinoso-Suárez, Reference Reinoso-Suárez and Schüller-Pérez2007). He is the most important Spanish scientist of all time (Delgado-García, Reference Delgado-García2006), and one of the most important figures in all the history of science (Anaya, Reference Anaya2002; Sánchez-Ron as cited in Fernández- Santarén, 2006).
It can also be said of Cajal, categorically, that he was an extraordinarily productive scientist. Consider a few examples to illustrate the point: (1) Gamundí, Timoner, Nicolau, and Langa (Reference Gamundí, Timoner, Nicolau, Langa, Gamundí and Ferrús2006) conducted an interesting analysis of Cajal’s growing number of publications over the course of his scientific career, reporting that between 1888 and 1914, at the height of his research, he published 267 works (76.7% of his work, for an annual mean of 9.8). Beginning in 1914 with the start of World War I, he lost his stride; still he continued to publish around six papers annually; (2) García-López, García-Marín, and Freire (Reference García-López, García-Marín and Freire2010) catalogued and analyzed 4,500 histologic slides prepared by the genius; (3) it is easily confirmed that copies of over 200 histologic drawings appear in Recollections of my Life (1923) alone. It was to this facet of Cajal, his enormous productivity, De Felipe (Reference De Felipe and Marín-Araguz2005) referred when he said:
A diferencia de otros grandes investigadores, Cajal no se limitó a realizar un único descubrimiento de gran importancia, sino que aportó numerosas e importantes contribuciones al conocimiento de la estructura y función del sistema nervioso. (…) Sus contribuciones son tan numerosas que resulta del todo imposible resumirlas en unas líneas.
[Unlike other great researchers, Cajal was not limited to one highly important discovery, instead he made numerous important contributions to our knowledge of the structure and functioning of the nervous system. (…) His contributions were so numerous it would be utterly impossible to summarize them in a few lines]. (p. 214)
His work was fascinating for its depth, usefulness, and impact, so it seems reasonable to ask – as a potential source of stimulus and learning for generations to come – how Ramón y Cajal became a genius. Anaya-Reig’s (2016) instrumental case study (Montero & León, Reference Montero and León2002) used narrative analysis of predominantly autobiographical material to pursue this question, maintaining that the histologist was not plotting his triumphant future in the world of Science as a child – he or his environment. Nor was his triumph the result of outstanding innate qualities, or sheer force of will – which he valued so highly –, what catapulted him to success. Like any other person, random chance influenced the course of his life, and there were fundamental things life served him that could not be planned. However his eyes were wide open, he knew how to make sure decisions at the right moment, and he took full advantage of the opportunities presented to him. He might have been a great artist, great writer, great photographer, or great chess player. He showed impressive ability in all those activities. But ultimately he decided to follow a different path and, immensely self-assured, he dedicated himself fully to its pursuit. His amazing contribution to science was made possible by his untiring work at self-construction, sustained by various psychosocial factors, such as tremendous self-regulation skills per Albert Bandura’s (1999) Social Cognitive Theory.
With that in mind, the present study shows that as a major part of a high-level, intellectual self-regulation strategy, Cajal deliberately studied scientists’ psychological features and was therefore a Psychology of Science scholar avant la lettre, a discipline which Feist (Reference Feist2006, Reference Feist2011) distinguished as an emerging branch of Psychology.
Cajal on scientists
The Nobel laureate’s interest in the psychology of scientists was essential along his path to success. For the Spanish histologist, potential triumph in research could come from determining what the best researchers are like, and then becoming like them (Anaya-Reig, Reference Anaya-Reig2016). A career in science meant overcoming obstacles, discipline in day-to-day work – what in The World from an Eighty-Year-Old’s Point of View (1934) he called “unbreakable will” (Ramón y Cajal, 2000, pp. 741–742)–, and knowledge of oneself and what the activity involves. Cajal knew himself, and when he was unsure what his work required of him, he made an effort to figure it out. What is needed to be a scientist? Referring to his early work, Cajal noted the importance of educating oneself alongside role models Footnote 1 :
Despite the mediocrity of the results, these attempts at research work were highly instructive to me. They led me to (…) a knowledge of the psychology of scientists. (…) Following from close at hand the plan of action and the steps employed by them to overcome the obstacles and snares with which nature seems to defend herself against human curiosity (…), the intellectual lucidity, the solid culture, the technical difficulties, and sometimes the brilliant findings of genius; but there appear also the prejudices, carelessnesses, and equivocations of the man of science. Once they are discovered, these little mistakes are very useful in that they possess the virtue of jolting the diffidence and inertia of the beginner. From the general checking up of books by comparison with the objects, I came to the conclusion that scientists – except in the rare cases of really great minds – are men like everybody else, without any advantage other than that of having prepared themselves adequately for investigation under the direction of illustrious teachers and in the lukewarm greenhouse of scientific schools. (Ramón y Cajal as cited in Fernández-Santarén, Reference Fernández-Santarén2006, pp. 353–354).
This question was further clarified long after Ramon y Cajal’s time, when Feist (2006, pp. 131–132) cited Harriet Zuckerman’s (1996) Scientific Elite about the Psychology of Science. In it, Zuckerman established the cumulative advantage of young scientists trained by Nobel laureates, compared to less celebrated scientists.
On another note, Cajal clearly recognized two key aspects of scientific work: a) differentiating theory from data; and b) the importance of data that contradict one’s theory – and being able to admit when you are wrong and revision is needed. Both those issues were raised in recent studies on the Psychology of Science (Feist, Reference Feist2006). On that note, regarding the critical distinction between theory and data, Cajal wrote, in a letter to Friar Zacarías Martínez:
The scientist must distinguish two things from one another: facts, and their interpretation. Facts are certain, and in their discovery lies my vainglory. There is much to say about physiological interpretation, and except for certain conditions that are naturally imposed, everything presented on the subject should be considered more or less plausible hypotheses. (Ramón y Cajal as cited in Durán-Muñoz & Alonso-Burón, 1983, p. 218)
Furthermore, on the importance of recognizing data that show one’s own equivocations:
If the hypothesis does not fit the data, it must be rejected mercilessly, and another explanation beyond reproach drawn up. Let us subject ourselves to harsh self-criticism that is based on a distrust of ourselves. During the course of proof, we must be just as diligent in seeking data contrary to our hypothesis as we are in ferreting out data that may support it. Let us avoid excessive attachment to our own ideas, which we need to treat as prosecutor, not defense attorney. Even though a tumor is ours, it must be removed. It is far better to correct ourselves than to endure correction by others. Personally, I do not feel the slightest embarrassment in giving up my ideas because I believe that to fall and rise alone demonstrates strength, whereas to fall and wait for a helping hand indicates weakness. (Ramón y Cajal, 1940, p. 185)
Though he was not an epistemologist, Cajal faithfully adopted the precepts of falsifiability that Karl Popper later developed in his falsifiability theory of science: guiding oneself by a science of “conjectures and refutations” – as Popper states in his (1963) book – and rejecting any hypotheses or theories disproven by the data. The scientist should him or herself seek refutation, and submit hypotheses to rigorous testing. This Cajal prescribed in no uncertain terms, sixty four years prior to the publication of Popper’s book.
Moreover, knowing the value of empirical data, Cajal tried to accumulate evidence regarding the psychology of scientists, and draw conclusions from it. Below we pose some clear examples to test our hypothesis that his psychological knowledge of scientists was not based purely on speculative reflection; no, he investigated this subject and others because they interested him tremendously. Accordingly, Cajal’s “thoughts about general methods” in research suggests:
It would not be wise in discussing general principals of research to overlook those panaceas of scientific method so highly recommended by Claude Bernard, which are to be found in Bacon’s Novum Organum and Descartes’s Book of Methods. They are exceptionally good at stimulating thought, but are much less effective in teaching one how to discover. After confessing that reading them may suggest a fruitful idea or two, I must further confess an inclination to share De Maistre’s view of the Novum Organum: «Those who have made the greatest discoveries in science never read it, and Bacon himself failed to make a single discovery based on his own rules». Liebig appears even more harsh in his celebrated Academic Discourse when he states that Bacon was a scientific dilettante whose writings contain nothing of the processes leading to discovery, regardless of inflated praise from jurists, historians, and others far removed from science.
(…) Reading the work of the great scientific pioneers such as Galileo, Kepler, Newton, Lavoisier, Geoffroy Saint-Hilaire, Faraday, Ampere, Bernard, Pasteur, Virchow, and Liebig is considerably more effective. However, it is important to realize that if we lack even a spark of the splendid light that shone in those minds, and at least a trace of the noble zeal that motivated such distinguished individuals, this exercise may if nothing else convert us to enthusiastic or insightful commentators on their work – perhaps even to good scientific writers – but it will not create the spirit of investigation within us.
A knowledge of principles governing the historical unfolding of science also provides no great advantage in understanding the process of research. Herbert Spencer proposed that intellectual progress emerges from that which is homogeneous and that which is heterogeneous, and by virtue of the instability of that which is homogeneous, and of the principle that every cause produces more than one effect, each discovery immediately stimulates many other discoveries. However, even if this concept allows us to appreciate the historical march of science, it cannot provide us with the key to its revelations. The important thing is to discover how each investigator, in his own special domain, was able to segregate heterogeneous from homogeneous, and to learn why many of those who set out to accomplish a particular goal did not succeed. (Ramón y Cajal, 1940, pp. 17, 19–20)
It is fitting to mention here the distinction drawn by positivist Hans Reichenbach in 1938, between the context of justification and the context of discovery, in his Experience and Prediction – a work certainly unknown to Cajal since he died four years before its publication. Once more ahead of his time, he called for a thorough understanding of scientific activity. As the German physicist and thinker described in that work:
El acto de descubrimiento escapa al análisis lógico (…). La tarea del lógico no es dar razón de los descubrimientos científicos; todo lo que le incumbe es analizar la relación existente entre los hechos dados y una teoría que se presente con la pretensión de explicarlos. En otras palabras, a la lógica solo le importa el contexto de justificación.
[The act of discovery escapes logical analysis. (…) It is not the logician’s task to account for scientific discoveries; all he can do is to analyze the relation between given facts and a theory presented to him with the claim that it explains these facts. In other words, logic is concerned only with the context of justification] (Romo, Reference Romo2008, p. 89).
Still, this lucid distinction had no epistemological impact on the study of science until that study itself became scientific, until meta-sciences were born, and most especially until the Psychology of Science’s birth as an independent discipline in the 80’s Footnote 2 . In effect, to analyze discovery is not the philosopher’s domain; some, like Popper, even defined it as the irrational moment of doing science. But certainly – irrational or not – without discovery there are no advances in science, and to explain that is in the purview of psychologists, who except in a few instances Footnote 3 , entered this area on tiptoes until the study of scientific creativity was established as a sub-field of the Psychology of Science.
Regarding Cajal’s fierce criticism of Francis Bacon, let us recall that Bacon’s inductive view of the scientific method in Novum Organum was a precursor to the predominant philosophy of science in Cajal’s time – logical positivism –; our Nobel laureate joined Albert Einstein in rejecting its prevailing mechanism. Touching on discovery, Einstein complained about systematic undermining of the study of what he called “the personal struggle.” To be sure, neither Novum Organum nor the work of 20th century positivists could in Cajal’s words “teach discovery,” and more than a hundred years after he wrote Advice for a Young Investigator, we do well to recognize that the stories of scientists themselves taught Cajal more about discovery than the Philosophy of Science literature did. For instance, the strong intuitive sense of Henri Poincaré’s (1913) The Foundations of Science, Einstein’s (1949) Autobiographical Notes, Charles Nicolle’s introspection about his experience discovering typhoid transmission in Biologie de l’Invention (1932), and James Watson’s (1968) story The Double Helix: A Personal Account of the Discovery of the Structure of DNA all provide first-rate evidence, gathered through introspection, to test statements by psychologists of creativity regarding scientific discovery (Romo, Reference Romo1997).
We believe scientific genius is best understood using a case study approach. Howard Gruber’s (1984) thorough examination of the notebooks Charles Darwin kept between 1837 and 1839 set forth a constructivist model of creativity, and a methodology he sums up in the maxim “studying creative people at work.” It was the foundation for many subsequent case studies, and advanced our understanding of the phenomenon by leaps and bounds (Gruber, Reference Gruber1984; Gruber & Davis, Reference Gruber, Davis and Sternberg1988; Wallace & Gruber, Reference Wallace and Gruber1989; Gruber & Wallace, Reference Gruber, Wallace and Sternberg1999; Gardner, Reference Gardner1995). The case study method allows us to ascertain general constructs – mental processes and personal qualities that are characteristic of eminent geniuses – for later empirical testing through other methods, to analyze creativity in genius as well as the average person (Sternberg, Reference Sternberg1999).
On another note, Cajal’s astute observations led him to anticipate another epistemological construct, one that historian of science Thomas Kuhn would later define as essential tension, the tension between two contradictory forces related to one’s field: respect for the discipline in which the inventor-scientist was educated, and the need to break with it to make a new discovery. The latter requires theoretical reformulation, or even rupture, to build a new paradigm (Kuhn, Reference Kuhn and Helier1982). The Psychology of Science has reframed this process in terms of conceptual change (Giere, Reference Giere1988). Cajal experienced essential tension as follows:
It was incumbent on me to persuade the experts of good will and clear understanding. It was chimeric to expect unanimous applause. How was I to convince the researchers of old, committed in their defense of erroneous facts or groundless hypotheses? (Ramón y Cajal as cited in Fernández-Santarén, Reference Fernández-Santarén2006, p. 428)
He observed the same phenomenon in works by other distinguished scientists. In Advice, he states that:
Far from humbling one’s self before the great authorities of science, those beginning research must understand that – by a cruel but inevitable law – their destiny is to grow a little at the expense of the great one’s reputation. It is very common for those beginning their scientific explorations with some success to do so by weakening the pedestal of an historic or contemporary hero. By way of classic examples, recall Galileo refuting Aristotle’s view of gravity, Copernicus tearing down Ptolemy’s system of the universe, Lavoisier destroying Stahl’s concept of phlogiston, and Virchow refuting the idea of spontaneous generation held by Schwann, Schleiden, and Robin. This principle is so general and compelling that it is displayed in all areas of science and extends to even the humblest of investigators. If I might be so bold as to refer to myself in the company of such eminent examples, I should add that on initiating my own work on the anatomy and physiology of nervous centers, the first obstacle that had to be set aside was the false theory of Gerlach and Golgi on the diffuse nature of neural networks in the gray matter, and on the nature of nerve current transmission. (Ramón y Cajal, 1940, pp. 28–29)
Other analyses by Cajal, later confirmed, had to do with psychosocial aspects of metascience, like the so-called Matthew effect and the trajectory of a scientist’s productivity. For instance, in a section of Café Chats (1921) called “Advice to the Impatient,” Cajal describes his own version of the Matthew Effect (Merton, Reference Merton1968): frequent publication early in one’s career gets rewarded by the environment, and gives them access to more resources and support; that, in turn, helps them keep publishing more, and thus the cycle repeats. Nonetheless the Spaniard pointed out the considerable effort it takes to “produce just a little” early on, before one’s first original work is published; after that milestone, many subsequent works come with relative ease and speed:
You may find yourself depressed and ashamed because you recognize, on the verge of tears, that you must struggle a lot to produce just a little. This is what happens to everyone in the beginning, with only minor differences. But do not be disillusioned; work passionately. No matter how difficult it may be, you must locate the source of the first new truth. There, a river will suddenly appear, flowing swiftly and bountifully with other discovered facts. For in science there is only one harsh and painful effort: The birth of that first original fact. (Ramón y Cajal, 2000, pp. 500–501)
Likewise, again based on facts he observed in himself and other scientists, he noted: “the first discovery is the one that counts; the rest are usually corollaries of the original. A well-known doctrine espoused by philosophers such as Taine, and by scientists such as Tyndall (…)” (Ramón y Cajal, 1940, p. 118).
His rising number of publications, compiled in Recollections, perfectly fit the aforementioned effect, and with the discovery of the neuron came an avalanche of recognition: 1) between 1880 and 1887 Cajal published 11 works; 2) in 1888 – his discovery of the neuron appeared in the second work he published that year – 9 works; and 3) between 1888 and 1923, 232 works, including extensive books. As discussed in the section above, recent bibliographic literature confirmed this number of publications, or more, since additional works were published after the release of his autobiography (Gamundí et al., Reference Gamundí, Timoner, Nicolau, Langa, Gamundí and Ferrús2006).
On the other hand, Advice notes Cajal’s considerations of the trajectory of scientific productivity. To our understanding, they represent an early take on Simonton’s (2006) conclusion that there is a clear relationship – shaped like an upside-down “U” – between age and scientific productivity, quantitatively as well as qualitatively, such that natural scientists peak around forty years old, with productivity gradually decreasing thereafter. However, Cajal discussed two stages rather than three:
Two phases may often be noted in the careers of learned investigators. First there is the productive time devoted to the elimination of past errors and the illumination of new data, and it is followed by the mature or intellectual phase (which does not necessarily coincide with old age) when scientific productivity declines and the hypotheses incubated during youth are defended with paternal affection from the attacks of newcomers. (Ramón y Cajal as cited in Fernández-Santarén, Reference Fernández-Santarén2006, p. 29).
Furthermore, one result of his discoveries about the psychology of scientific geniuses was that Cajal himself tried to dismantle one of what are today called implicit theories of genius (Romo, Reference Romo1997). He tried “to upend the assertions of providentialism and exceptionalism concerning the origin of discoveries” (Ramón y Cajal, 1999, p. 16). Thus he said:
Some readers of this discourse have warned me that I place far too much emphasis on the discipline of will power and not enough on the exceptional attitudes of great investigators. I would be the last to deny that the greatest scientific pioneers belonged to an aristocracy of the spirit and were exceptionally intelligent, something that we as modest investigators will never attain, no matter how much we exert ourselves. Nevertheless, before making this concession – which is entirely justified – I continue to believe that there is always room for anyone with average intelligence and an eagerness for recognition to utilize his energy and tempt fate. Like the lottery, fate doesn’t always smile on the rich; from time to time it brings joy to the homes of the lowly. Instead, consider the possibility that any man could, if he were so inclined, be the sculptor of his own brain, and that even the least gifted may, like the poorest land that has been well cultivated and fertilized, produce an abundant harvest. (Ramón y Cajal, 1940, p. 8)
I could be mistaken, but conversations with illustrious scholars during my travels abroad led me to the sincere belief that most of them have normal intelligence, although it has been highly refined, and that they are driven by an ardent longing for fame. But more than that, on occasion I have met renowned scholars whose intelligence and emotional qualities are inferior to the very discoveries that raised them from obscurity – discoveries that were made through the blind and unexpected workings of chance. The example of Courtois is more common than many realize; one ingenious writer has pointed out that it is unclear whether he discovered iodine or iodine discovered him. (…) Many examples come to mind of an ordinary person, together with a culture of perseverance and alight with noble, patriotic passion, making true discoveries. But since there is nothing more irritating to men or nations than poverty of spirit, and no harsher judgment of the merit of a man’s work than attributing his success to stubborn consistency alone, allow me to avoid the reader’s resentment and angry recriminations, and offer myself up as an example. Without committing the sin of arrogance or presumption, I believe I can be considered the author of certain anatomical discoveries that, being amply tested and known, are cited as real contributions to science; (…) new knowledge is merely the fruit of work imbued with energy by the resolve and will to create something original. (Ramón y Cajal, 1972, pp. 82–84)
In another passage from Advice, Cajal was insistent in his determination to debunk the myth of genius:
Admittedly, certain concepts in science appear to be so complete, brilliant, and enduring that they seem to be the fruit of an almost divine intuition, springing forth perfect like Minerva from the head of Jupiter. However, the well-deserved admiration for such accomplishments would be considerably diminished were we aware of all the time and effort, patience and perseverance, trials, corrections, and even mishaps that worked hand in hand to produce the final success – contributing almost as much as the investigator’s genius. (Ramón y Cajal, 1940, pp. 26–27)
We must recognize the heuristic value of Cajal’s work in terms of his dual role as inventor-scientist and metascientist. In the first case, consider his biography, and how he modeled his career and social influences for the purpose of creativity in neurology – such that he could be defined as a self-made genius (Anaya-Reig, Reference Anaya-Reig2016). And analysis of his own creative processes, motivations, attitudes, and personal traits, documented in his numerous writings, are useful first-hand documents with which to examine different aspects of his creative genius in particular, and to gain a better understanding of scientific creativity in general (Anaya-Reig, Reference Anaya-Reig2016). In the second case, his dedication to understanding the key to scientific discovery and translating that knowledge into pedagogy for students in scientific vocations made him, as a psychologist, an applied as well as theoretical scientist. In this paper, we attempt to argue Cajal’s thesis – as we did at the beginning – using data we collected from his writings, and based on his activities to encourage young people to pursue research as a vocation in a country with considerable scientific draught, as Spain was in his time.
Creative thinking according to Cajal
Examining specific aspects of Cajal’s reflections on the cognitive processes involved in creative thinking, we found these quotes where he ratifies other scientists’ contributions. Of Poincaré’s writings, he noted:
As Poincaré says in his beautiful book, La Science et la Méthode: «Intellectual beauty is sufficient unto itself, and only for it rather than for the future good of humanity does the scholar condemn himself to arduous and painful labors». (Ramón y Cajal, 1940, p. 88)
Of Pierre-Simon Laplace’s writings, he wrote: “As Laplace has pointed out, to discover is to bring together two ideas that were previously unlinked” (Ramón y Cajal, 1940, p. 90). From Wilhelm Ostwald’s book Great Men, he mined the following words, calling them “judicious and generally correct”:
«The most important quality of the scholar is originality, that is, the ability to picture something beyond what is taught. Precision in one’s work, self-criticism, conscientiousness, knowledge, and skill are also necessary, but all can be acquired later through suitable education». (Ramón y Cajal, 1940, pp. 216–217).
Furthermore, Cajal clearly investigated the matter of scientists’ psychology as a strategy to pursue the path of success. It was not just its relationship to intelligence and education, and their relation, in turn, to the fine brain structure the histologist was researching Footnote 4 ; he was documented reading psychology texts on talent as well as genius. To that point, he left written notes indicating he thought it was most people’s opinion that “talent is facility, and genius originality.” Café Chats, for instance, cites William James on genius: It is “an unusual development of association by similarity” (Ramón y Cajal, 2000, p. 425). And without skipping a beat:
We tend to consider talent and genius as perfectly defined, discreet human varieties, setting aside the stages in-between. Between the ordinary mind and heroic understanding, there may be clarity or preparedness; by the same token, genius and talent are (sometimes) peppered with originality. If the psychology of ordinary minds and lackluster individuals interested experts as much as literary or scientific genius, a rich, nuanced gamut would likewise have been discovered between prudent mediocrity and radical idiocy. (pp. 424–425)
Underlying all these quotations are the principles considered the ABC’s of the Psychology of Creativity discipline. First: highlighting originality as a defining criterion for discovery. Cajal accepts the role of two basic criteria for defining creative output: originality and value. In discussing originality, he not only acknowledges a new science concept’s novelty, but its relevance to the discipline.
In addition, he wisely monitored the cognitive functions that best define the process of invention. Thus, in discussing the spirit of inquiry or self-criticism, he was in a way verbalizing what Getzels and Csikszentmihalyi (Reference Getzels and Csikszentmihalyi1976) empirically defined in their Problem Finding model, and which the literature accepts as the first step in the creative process: looking for problems. This was covered in Joy Paul Guilford’s (1959) earliest models of divergent thinking. Other science geniuses, such as Einstein, discerned this; they understood that advances in science mean proposing new questions, new possibilities, looking at old problems from a new point of view – and that to do so requires creative imagination (Einstein & Infeld, Reference Einstein and Infeld1938).
Similarly, earlier texts suggest that Cajal valued the ability to associate ideas, in keeping with the widely recognized importance of associative processes, that is, processes that connect disparate ideas, even from conceptually very different fields. An approach which behaviorist associative models proposed to explain creativity (Mednick, Reference Mednick1962), and that was later considered one of the basic strategies to elicit creative insight in the process of invention, in all its aspects: analogical reasoning. An ability to think in combination, it is not always produced consciously, and gives way to that happy idea in which the whole process culminates (Gruber, Reference Gruber1984; Holyoak & Thagard, Reference Holyoak and Thagard1996). By way of example, analogy played an important role in discoveries by August Kekulé (snakes and atoms), Isaac Newton (apples falling and gravitational forces), and William James (flowing rivers and mental experience).
But that is not all. The following paragraphs from Advice (1899) could themselves be considered part of a manual for the Psychology of Creativity, in terms researchers currently use to show how processes of invention occur in science:
To bring scientific investigation to a happy end once appropriate methods have been determined, we must hold firmly in mind the goal of the project. The object here is to focus the train of thought on more and more complex and accurate associations between images based on observation and ideas slumbering in the unconscious – ideas that only vigorous concentration of mental energy can raise to the conscious level. One must achieve total absorption; expectation and focused attention are not enough. We must take advantage of all lucid moments, whether they occur during the meditation following prolonged rest; during the super-intense mental work nerve cells achieve when fired by concentration; or during scientific discussion, whose impact often generates unanticipated intuition like sparks from steel.
(…) During the so-called intellectual incubation period, the investigator should ignore everything unrelated to the problem of interest, like a somnambulist attending only to the voice of the hypnotist. In the lecture room, on walks, in the theater, in conversation, and even in reading for pleasure, seek opportunities for insight, comparisons, and hypotheses that add at least some clarity to the problem one is obsessed with. Nothing is useless during this process of adjustment. The first glaring errors, as well as the wrong turns ventured on by the imagination, are necessary because in the end they lead us down the correct path. They are part of the final success, just as the initial formless sketches of the artist are a part of the finished portrait.
When one reflects on the ability that humans display for modifying and refining mental activity related to a problem under serious examination, it is difficult to avoid concluding that the brain is plastic and goes through a process of anatomical and functional differentiation, adapting itself progressively to the problem. The adequate and specific organization acquired by nerve cells eventually produces what I would refer to as professional or adaptational talent. As a motivator of the will itself, this brain organization provides the energy to adapt understanding to the nature of the problem under consideration. In a certain sense, it would not be paradoxical to say that the person who initiates the solution to a problem is different from the one who solves it. This is an obvious and simple explanation for the astonishment proclaimed by all investigators on discovering the simple solution so laboriously sought. “Why didn’t I think of this at the outset!” we exclaim. “There was so much confusion traveling down roads that led nowhere!” (Ramón y Cajal, 1940, pp. 61–64)
Here Cajal clearly alludes to the long and fitful process of insight generation, which Gruber later described in his famous examination of Darwin’s (1981/1984) work. It is also interesting to note how Cajal refers to the slow, laborious process of reflection, of constant “worry,” as “intellectual incubation.” In so doing, he emphasizes that the process continues while resting from work, by taking it with you wherever you go, helping to bring about a successful solution to the research question. Cajal’s words unavoidably invokes Olton’s (1979) experimental studies of incubation and the concept of “creative worrying;” that author coined the term in reference to the same process Cajal described eighty years prior. In those moments Olton defined somewhat prosaically as time-aside periods, having recovered from fatigue and mental blocks, we return to the problem again and again, allowing for insight to emerge and culminate in the process of invention.
Conversely, in discussing intellectual “incubation,” Cajal posits that the unexpected moment of discovery may occur thanks to cerebral plasticity, because of a gradual neuronal reorganization produced by focused work on a subject. Incubation is a technical term Graham Wallas used in his 1926 The Art of Thought Footnote 5 to capture what he considered the second stage in the creative process. It is the need to disconnect from work, and rest, in order to suddenly solve the problem thanks to the working of the unconscious mind. Today Psychology recognizes incubation as a state of latent preoccupation while resting from the question of interest; it can occur during creative activity but is not always unconscious, nor completely necessary (Romo, Reference Romo1997).
Also, building on the phases of the creative process Wallas described, which with some modifications still apply today (Csikszentmihalyi, 1996/2006), we must also note the importance Cajal attributed to the moment of illumination that culminates the process, described as “unanticipated intuition like sparks from steel.” Cajal was also anticipating scientific interpretations of cognitive psychology by attributing an important role to associative processes in its appearance, encouraged by that earlier incubation phase and by mental flexibility. Mental flexibility enables one to overcome the mental blocks that impede insight (Sternberg & Davidson, Reference Sternberg and Davidson1995): “Why didn’t I think of this at the outset!” we exclaim. “There was so much confusion traveling down roads that led nowhere!” But, good student of the brain as he was, Cajal explains the neurological correlate: “the brain, by virtue of its plasticity, develops anatomically and dynamically, gradually adapting itself for the subject.” And the motor for that process is willpower itself, he tells us, but that concerns other, non-cognitive dimensions of invention he also studied, which we will analyze below.
Cajal was insistent on another point, about something corroborated in Psychology since his time, and that is the important role random chance can play when a person knows how to take advantage of it:
In science as in the lottery, luck favors he who wagers the most – that is, by another analogy, the one who is tilling constantly the ground in his garden. If Pasteur discovered bacterial vaccines by accident, he was assisted by genius. He envisioned all of the benefits that might be derived from a casual observation, the reduced virulence of a bacterial culture exposed to air (probably reduced by the action of oxygen).
The history of Science is full of similar tales. Scheele happened upon chlorine while trying to isolate manganese; Claude Bernard planned experiments to characterize the destructive agent in sugar but instead discovered the glycogenic function of the liver; and so on. To end this section, we shall consider two recent examples of almost miraculous good luck in the stupendous discoveries of Roentgen, Becquerel, and the Curies. (Ramón y Cajal, 1940, pp. 113–114).
Roberts (1989/1992, p. 14) wrote to similar effect in Serendipity. Accidental Discoveries in Science, suggesting many people have acknowledged the impact of random chance in their discoveries, referencing Pasteur’s famous saying: “In the field of observation, chance favors the prepared mind.” Thus it can be said that there are cases of accidental discovery, but less.
Other psychosocial and personality aspects of scientists, according to Cajal
The histologist’s interest in determining the psychosocial features of wise men clearly started with his objective to master research, so he recorded abundant observations. He amassed them like a guide to his work, writing them down for the benefit of others (Anaya-Reig, Reference Anaya-Reig2016). In that sense, Advice (1899) could very well be considered more than “un tratado pedagógico para dar aliento a la juventud estudiosa (…) tan útil hoy como cuando fue escrito” [a pedagogical attempt to inspire young scholars (…), as useful today as when it was written] (Ramón y Cajal-Junquera, 2000, p. 81), but instead as a pioneering work in this subdiscipline of Psychology, at least in the Spanish context, and one that indeed remains very useful today. We call Advice “pioneering” because its first edition, based on the 1897 speech he gave when he was inaugurated into the Royal Academy of Exact, Physical, and Natural Sciences, fell chronologically between Francis Galton’s English Men of Science (1874) and Anne Roe’s The Making of a Scientist (1953). Feist (Reference Feist2006) and Ardila (Reference Ardila2005), respectively, posited that those were pioneering texts in the Psychology of Science.
This passage from the work cited above shows that: “Indispensable qualities for the research worker include independent judgment, intellectual curiosity, perseverance, devotion to country, and a burning desire for reputation” (Ramón y Cajal, 1940, p. 55). And the same can be said of his statement that an investigator is “captivated by originality, (…) and in short, he is capable of all sorts of sacrifices to achieve the noble dream of giving his own name to some new star in the firmament of knowledge. (Ramón y Cajal, 1940, p. 220). Except for patriotism Footnote 6 , the qualities the Nobel laureate described have been proposed as characteristic personality traits of scientists (Ardila, Reference Ardila2005; Feist, Reference Feist2006; Romo, Reference Romo2008): they show perseverance in their work and overcome obstacles, they are highly motivated to succeed, and they are introverted. Regarding that last feature, since one’s specific field of expertise largely determines what features are associated with creativity (Kaufman & Baer, Reference Kaufman and Baer2005), we should clarify that introversion is more closely associated with natural scientists’ behavior than social scientists’ behavior. They are also curious, original, and independent. Cajal’s definition of personality in scientists preceded modern studies of Paul Costa and Robert McCrae’s (1985) five-factor model, in which the trait openness, which encompasses these characteristics, is usually what best defines creative people in any field (Kaufman, Reference Kaufman2009).
Regarding perseverance in work, it seems apropos to point out this is recurring idea in Cajal’s work. He argues that persistent thinking about one’s subject of study helps bring a scientific investigation to a good end, not just in Advice (Ramón y Cajal, 1940), cited in the direct quote above, but elsewhere too. In Recollections, for instance, he wrote:
If, anyhow, scientific discovery is due no more to genius than to chance, then we can all be inventors. To do so, it is enough to play obstinately and persistently on one and the same number in this lottery. It is entirely a question of patience and perseverance. (Ramón y Cajal as cited in Fernández-Santarén, Reference Fernández-Santarén2006, p. 226).
In his pedagogical and democratizing efforts in science, in his struggle to show that anyone of normal intellectual aptitude and deep love, dedication, and perseverance in their work can attain the highest honors in science, Cajal cited the humble origins of countless geniuses. Lewy (Reference Lewy1987), who was his personal secretary for so many years, wrote this of Cajal’s childhood:
El origen humilde de nuestro sabio es de sobra conocido. (…) Cajal tenía a gala que sus antecedentes fueran labradores y tejedores. Siendo ya anciano, leyó una obra de Stockard “The physical basis of personality”, editado en 1931, apuntando en sus márgenes, como él solía hacer en los libros de su biblioteca: “Muchos de los grandes hombres de ciencia, la literatura y el arte, fueron hijos de trabajadores pobres. Así Shakespeare –hijo de un carnicero-, Demóstenes –de un herrero; Cervantes, de un barbero sangrador, Mòliere; de un tapicero, Kepler, de un posadero, etc.
[Our wise man’s humble origin story we know all too well. (…) Cajal was proudly descended from farmers and weavers. Already an old man, he read Stockard’s The Physical Basis of Personality, edited in 1931, and noted in the margins, as he often did the books in his library: “Many great men of science, literature, and art were children from poor, working-class families. Shakespeare was the son of a butcher, Demosthenes – a blacksmith; Cervantes – a barber surgeon; Mòliere – an upholsterer; Kepler – an innkeeper, etc.] (p. 26).
Furthermore, judging from his inquisitive work in science and from personal experience, he reported that science is often conducted with limited means. He added, nonetheless, that it is no excuse to give up:
We could cite dozens of classic examples of modest beginnings. Faraday was an apprentice to a bookbinder when he was carried away by an enthusiasm for science and joined Davy’s laboratory as a helper or mechanic. On leaving the laboratory (and not having followed a path to any particular career), he set up a research center that produced a host of admirable conquests – breathing new life into the science of electricity. The great Berzelius began his chemical discoveries in the workshop of his drugstore. Many of the greatest astronomers explored the sky from the rooftops of their homes, armed with mediocre telescopes. Goldschmidt provides a nice example. From the window of his room, aided only by a very small refracting telescope (105mm), patience allowed him to discover a great many asteroids. (Ramón y Cajal, 1940, pp. 146–147)
In Recollections (1923), the genius included a personal reflection on his dedication to Histology. It makes for a clear first-person example, related to the quotation above:
The path of histology condemned me absolutely to poverty, in recompense for which, if I should be successful, the only prospect to invite me was the cold praise or the lukewarm and critical respect of two or three dozen savants (…). Nevertheless, influenced by my own inclinations and especially by motives of an economic nature, I finally chose the cautious path of histology, the way of tranquil enjoyments. I knew well that I should never be able to drive through such a narrow path in a luxurious carriage; but I should feel myself happy in contemplating the captivating spectacle of minute life in my forgotten corner and listening, entranced, from the ocular of my microscope, to the hum of the restless beehive which we all have within us. As for the economic reason referred to, it was nothing else than the expensiveness of bacteriological work (Ramón y Cajal, as cited in Fernández-Santarén, Reference Fernández-Santarén2006, pp. 368–369).
The topics covered in the last two paragraphs are further evidence of Cajal’s fine intuition for what Amabile and Hennessey (Reference Amabile, Hennessey and Sternberg1988) would later define as the principle of intrinsic motivation for creativity, so often cited in experimental, psychometric, and case studies. It maintains that people are more creative when they feel motivated by the interest, pleasure, satisfaction, or challenge of the work, and not by external pressures. Above, Cajal alludes to his love and enthusiasm for science. And a line in Café Chats reads: “Let the vicious and idle say what they choose. Agreeable and useful work remains the best of distractions” (Ramón y Cajal, 2000, p. 489).
Or when he says in Tonic of the Will (Ramón y Cajal, 1940, p. 49) that anyone who ardently wants talent will have it – “One might say that work substitutes for talent, or better yet that it creates talent” – he foresaw what Amabile would later develop into her componential model of innovation. The most important component is task motivation; with that firmly established, the inventor can develop the requisite skills for their specific field, and the skills needed to generate creativity. Without motivation, good aptitude alone does not ensure creativity (Amabile, Reference Amabile1983, Reference Amabile1996).
Analyzing psychosocial aspects of creativity more in-depth, Cajal was abundantly clear in his stance about the connection between creativity and disorder, one of the most widely disseminated implicit theories of creativity (Romo, Reference Romo2003). To put a stop to that recurring, popular explanation of genius, he wrote:
The genius tends to excuse his own lethargy and mediocrity because he considers himself to be a pathological case. Behold, a cheap and easy consolation. I will concede, however, that many of the greatest intellects and brightest talents have temporarily or permanently fallen into the depths of insanity. But what about the other factors that might influence this mental imbalance...work-related exhaustion, abuse of stimulants, unstoppable, vehement passion, and frankly, the effects of syphilis spirochete, notorious for causing general paresis? (…) The more advanced intellectual work requires two conditions: a good thinking engine and an ample supply of coal (the will). Unfortunately, these are not always combined in great men. (Ramón y Cajal, 2000, p. 428)
The Spanish histologist raised another question, addressed by the field of Psychology many years later: generally speaking, scientists receive a religious education, but religion does not hold a prominent place in their lives thereafter (Roe as cited in Ardila, Reference Ardila2005; Feist, Reference Feist2006):
A wise man, religious as he may be, gains more in an environment of free spiritual expansion. Moreover, we believe that presently (with notable exceptions), the men most occupied with the problems of the world are least preoccupied with heavenly blessings. (Ramón y Cajal, 1940, p. 252).
Didactic application of Cajal’s psychological analysis
We conclude by exploring what was for Cajal the most important applied dimension of his laborious, thorough analysis of the nature of science and the psychology of scientists: pedagogy. In addition to providing useful research tips, he made an effort to encourage people who want to dedicate their lives to investigation but feel their strength wavering (Ramón y Cajal, 1940, pp. 9, 21–22). And it was entirely intentional, because by studying the best and observing himself Footnote 7 , Cajal had discovered various aspects’ importance to scientific research (Anaya-Reig, Reference Anaya-Reig2016), listed below. The Nobel laureate gave examples to illustrate each factor, and described them in the following terms:
a) High capacity for self-regulation (Anaya-Reig, Reference Anaya-Reig2016). Self-regulation was essential to Cajal’s work, and he was well aware of it, because he was a great thinker and knew himself well:
My father (…) with his blood he transmitted me traits of character to which I owe everything that I am: a profound belief in the sovereign will; faith in work; the conviction that a persevering and deliberate effort is capable of molding and organizing everything, from the muscle to the brain, making up the deficiencies of nature and even overcoming the mischances of character – the most difficult thing in life. (Ramón y Cajal as cited in Fernández-Santarén, Reference Fernández-Santarén2006, p. 100).
So he was insistent in his writings on the subject; he tried to make people see that while intelligence is important to success, the key is continuous effort above all, long term, what he called will. He could have said nothing on the subject, to cultivate – even more if possible – the mystery and myth of the unparalleled intellect. Instead, he showed honor and tremendous intellectual generosity, and wrote with amazing clarity. He did not discuss self-regulation as such, in Bandura’s (1999) terms, but attested to its crucial role in the achievement of any goal:
This advice is aimed more at the spirit than the intellect because I am convinced, and Payot wisely agrees, that the former is as amenable to education as the latter. (Ramón y Cajal, 1940, p. 22).
If there is anything truly divine in us, it is our will. With it we affirm our personality, temper our character, challenge adversity, correct our brain, and overcome ourselves day after day. (Ramón y Cajal, 2000, p. 487)
Therefore, we agree with Gutiérrez-Zuloaga (Reference Gutiérrez-Zuloaga and Cientifica2002) in asserting that Cajal is a magnificent example of how education, and self-education, can develop the will to do science. Modesto Bargalló argued the same in 1923: “la vida y la labor de Cajal eran «un esfuerzo viviente de autoeducación»” [the life and labor of Cajal was «a living example of self-education»] (López-Ocón Cabrera, 2007, p. 25).
b) Similarly, notice that Cajal particularly emphasized perseverance, considering the need to dedicate long years to a narrow subject in order to do excellent, productive work:
Even those with modest intellectual abilities will gather some fruit, provided they maintain faith in the creative power of education and devote extended periods of time to thorough analysis of a focused topic. (Ramón y Cajal, 1940, p. 48)
All great work is the fruit of patience and perseverance, combined with tenacious concentration on a subject over a period of months or even years. Many illustrious scholars have confirmed this when questioned about the secret of their creations. Newton stated that he arrived at the sovereign law of universal attraction only by constant thinking about the same problem, Darwin achieved such a high degree of concentration on the biological facts related to the principle of evolution that for many years he systematically deprived himself of all reading and contemplation unrelated to the goal of his thoughts. Buffon said unreservedly, «Genius is simply patience carried to the extreme». To those who asked how he achieved fame he replied: «By spending forty years of my life bent over my writing desk». As a final example, it is widely known that Mayer, the genius who discovered the principle of energy conservation and transformation, dedicated his entire life to this concept. (Ramón y Cajal, 1940, pp. 69–70)
On this point, too, Cajal was ahead of his time, presaging the “10 year rule” (Hayes, Reference Hayes1981; Gardner, Reference Gardner1995; Romo, Reference Romo2007), though he suggested a different timeframe from the one later verified.
c) High intrinsic motivation in one’s activity (Amabile, Reference Amabile1983, Reference Amabile1996):
I believe that all outstanding work, in art as well as science, results from immense zeal applied to a great idea. (Ramón y Cajal, 1940, p. 22)
(…) ideas do not show themselves productive with those who suggest them or apply them for the first time, but with those persevering workers who feel them strongly and put all their faith and love in their efficacy. From this point of view, it may be affirmed that scientific accomplishments are creations of the will and rewards of ardor. (Ramón y Cajal as cited in Fernández-Santarén, Reference Fernández-Santarén2006, p. 403).
Discussing intellectual work, Unamuno exclaimed: we are like «these spiders spinning those floating threads out of their own entrails». In effect, weak and mediocre will be the author’s work who did not weave it with the fibers of his heart, and thread from his own mind. (Ramón y Cajal, 2000, p. 500)
d) High capacity to learn through modeling (Anaya-Reig, Reference Anaya-Reig2016). Cajal recognized the impact of modeling on his life’s work. For example, referring to his medical education, he recalled:
Knowing my father’s enthusiasm for anatomy and his pronounced vocation for teaching (…). As the method demands, in order not to get lost in the inextricable thicket of vessels and nerves, we used to work with the books open before us, guided by Cruveilhier and by Sappey. (…) I derived much advantage from that teacher and method of learning (…). (Ramón y Cajal as cited in Fernández-Santarén, Reference Fernández-Santarén2006, pp. 250–251)
Again consistent with his own observations, Cajal highlighted this in his science work. Clearly aligned with aspects Bandura (Reference Bandura, Pervin and John1999) posited much later on in Social Cognitive Theory, Advice asserts that modeling is an important, intentional strategy for learning and attention, and is a psychological process necessarily involved therein. He also alluded to the fact that outcomes from this type of learning are not mere copies of the original. He explained it as follows:
Monographs by outstanding authors who have contributed most to a field should be submitted to thorough and critical study. Among other qualities, original talent has the great virtue of stimulating thought. A feature of every good book is that it allows the reader not only to extract the ideas deliberately presented by the author but also to formulate completely new ideas (different for each reader) that result from a conflict between our own fund of ideas and views expressed in the text. Clearly, the good treatise is an effective reagent for our cerebral energies, in addition to being an excellent source of scientific lore.
Human brains, like desert palms, pollinate themselves at a distance. However, for the union of two minds to occur and generate fruitful results through a book, the reader must become fully absorbed in what a master has written, must penetrate fully in its meaning, and finally must develop an affection for the author. (…).
Our new and inexperienced man of science must flee from abstracts and syllabuses as if from the plague. (…).
In the name of clarifying and popularizing someone else’s work he who does the abridging ends up substituting his own personality for that of the author, whose intellectual character – which is so interesting and educational for the reader – remains in the shadows. (Ramón y Cajal, 1940, pp. 101–103).
In less detail, and without drawing a relationship to Cajal’s earlier observations about the psychology of scientists, two works in the literature to date pose the same question we are undertaking here, more or less superficially: a) Ibarz-Serrat (Reference Ibarz-Serrat1994) suggested that according to Cajal, conscientiously reading great scientists’ work helped him consolidate his brilliant talent, and b) Gutiérrez-Zuloaga (2002, p. 217) indicated that the conditions the histologist prescribed to be a good investigator include “la conveniencia de conocer la obra de los grandes sabios, para desear imitarla” [the advantage of familiarity with eminent masters’ work, wishing to emulate them].
It is logical, in light of his discoveries, that the Nobel laureate did not resign himself to advising beginners, that he extended his recommendations to renowned scientists, impressing upon them Footnote 8 : a) that they should exercise expertise to be a model for those who are just starting out (Ramón y Cajal, 1940); b) that in their role as educators, they should gather biographical information about illustrious researchers and share it with apprentices, to teach willpower and prompt them to imitate the greats (Ramón y Cajal, 1940); c) the “transformative power of imitation” – emulating the masters is one of the qualities that help distinguish a disciple from others as likely to triumph. Cajal referenced additional characteristics to guide educators: The young researcher with a likelihood of success often “is overly timid,” “is also distinguished by a rigid worship of truth, and by a sound and genuine skepticism,” “is ambitious” for “he is eager to remove himself from the atmosphere of the ordinary and link his name to some great enterprise,” “is untiringly perseverant” to the point of stealing time and money from other activities for the sake of science, has “the shrewdness to track down rich lodes of knowledge,” and is “captivated by originality” and “indifferent to material gain and ordinary pleasures” (Ramón y Cajal, 1940, pp. 217–220).
In closing, regarding those final pieces of advice, please note that by offering them, Cajal points to a new and innovative facet of the psychology of science, an applied area of this burgeoning Psychology subdiscipline. Consider, as Feist suggested (2006), that understanding the scientist’s psychological processes, especially the best scientists’ psychological processes, could help identify which young people would be the finest scientists of future generations.
Conclusions
Cajal’s greatness affected the field of Psychology, too. In his self-regulation effort, he studied the psychology of wise men and conducted extensive self-observation to ascertain what psychosocial factors favor success in science. His findings led him to conclude that in most cases, there was nothing magical or supernatural in great researchers; instead, the basis for their achievements was largely arduous, patient, and methodical work, often learned under the tutelage of excellent scientists.
Acknowledging Cajal’s contributions to this nascent discipline is not only just; it could open up new directions for research in Psychology derived from his work. For good reason, Cajal remains among the most cited authors in neuroscience. Perhaps that could extend to Psychology as well if his work were reviewed for “current” psychological content so far unnoticed or unused. To paraphrase Runco and Jaeger’s (2012) recent writing on the definition of creativity, all research builds on other research, so the search for originality does not justify ignoring pertinent earlier contributions.
Various authors have definitively shown that Cajal addressed psychological issues, at times explicitly referring to his contributions to Psychology (Carpintero, Reference Carpintero2004; Gamundí, Rial, Nicolau, & Timoner, Reference Gamundí, Rial, Nicolau and Timoner1995; Ibarz-Serrat, Reference Ibarz-Serrat1994, Reference Ibarz-Serrat, Gamundí and Ferrús2006; Ibarz-Serrat & Villegas-Besora, 2001; Pérez-Hernández, Reference Pérez-Hernández2006; Ramón y Cajal-Junquera, 2002); Psychiatry (Baca-Baldomero, Reference Baca-Baldomero, Segovia de Arana and Albalat-Criado2007; López-Muñoz, Álamo, & Molina, Reference López-Muñoz, Álamo and Molina2010); and Pedagogy (Fernández-Santarén, Reference Fernández-Santarén2006; Gutiérrez-Zuloaga, Reference Gutiérrez-Zuloaga and Cientifica2002; López-Ocón Cabrera, 2007). Yet his contributions to the Psychology of Science in the form of instructive, exploratory essays and autobiographical texts have gone unrecognized. And although his “psychology of wise men” was not formed systematically, like doctrine – even in Advice – we believe the present work presents sufficient empirical evidence for the Spanish histologist to be considered a pioneer in the Psychology of Science, given that so many of his observations were later clearly corroborated in the discipline.
