The first of a pair of volumes devoted to the interior states of ancient Greek worshippers, this book makes provocative claims: first, that in order for a ritual to be efficacious, it was necessary for worshippers to approach the gods with a correct mental attitude and inner purity of thought, and second, that this principle was part of the ‘mainstream of Greek religion’ (p. 77), if not a form of orthodoxy. Third, P. and P. argue that ‘the moral dimension of purity and pollution had always formed an integral part of the Greek purity doctrine’. In their view, the observable shift in the fourth-century evidence is due to the increased volume of epigraphic evidence, the impact of Plato and the growing influence of Egyptian, Jewish and other traditions which emphasised inner purity.

P. and P. are quite correct to suggest that ritual purity often possessed a moral dimension, yet it was more limited than they suppose. To knowingly enter a sanctuary while polluted was disrespectful to the gods, so that even the bodily forms of pollution, in addition to the forms generated by wilful moral transgression, could be implicated in impiety. However, it is also the case that in Archaic thought, both bodily pollution and pollution generated by violating certain moral norms, for which the gods were guarantors, could be incurred inadvertently (Oedipus is the most famous example of the latter) and inflicted on the gods involuntarily. In general, P. and P. do not address the cases which challenge their thesis of a consistent cultural alignment of morally correct attitudes with ritual purity, and immoral attitudes with ritual impurity.

In Part 1, ‘An Epic View’, P. and P. adduce a single passage of Hesiod (Op. 737–41) to argue that for him ritual efficacy requires an inner purity of thought, which is policed by the gods. In his compendium of instructions for behaviour, Hesiod says that the gods resent and cause trouble for anyone who crosses a river ‘unwashed as to his badness and his hands’ (kakotêt’ ide cheiras aniptos). Although P. and P. make a convincing case that Hesiod associates the term kakotês with moral deviance, and thus that the zeugma here describes an irreverent individual who wilfully crosses a river without stopping to wash his hands or pray, they do not demonstrate convincingly that Hesiod's gods scrutinise the thoughts of worshippers for unspoken impiety. True, at Op. 256–62, Dike ‘reports the mind (noos) of unjust men’ to her father Zeus, but this follows immediately upon their crooked speech (258; cf. 261–2). Likewise at 755–6, the gods resent those who ‘find fault’ with sacrifices, but the verb mômeuein is normally used to refer to criticism spoken aloud. That is, Hesiod expects the anger of the gods to be directed at those who are immoral, but this immorality is detected through their actions and words (failing to wash hands, speaking crooked judgements, finding fault with sacrifices), not through mind-reading. The evidence does not warrant the conclusion that Hesiod represents ‘inner impurity’ as a state of concern to the gods separately from the externally visible/audible actions to which it gives rise. The failure to make this distinction is recurrent throughout the book, with words spoken aloud often equated to thoughts; for example, P. and P. cite Eur. El. 1350–6, on oath-breakers and perjurers, to show that the gods are mind-readers. In fact, the preponderance of evidence (e.g. the Greek preference for spoken rather than silent prayer) indicates that such a belief was not the default, but a reflective development applied only in specific situations.

In Part 2, which treats the Presocratic philosophers, P. and P. plausibly suggest that Pythagoras gave inner purity in worship contexts as much weight as words and deeds. If indeed Pythagoras was criticising the mainstream attitudes and practices of his day, however, the line of argument does not imply that ‘inner purity’ at the altar was a widespread concern, but the opposite. Part 3, ‘Inner Purity and Pollution in Sympotic Settings’, deals with Xenophanes and the Theognidea. P. and P. show how Xen. fr. 1 DK juxtaposes various forms of ritual purity in the symposium with correct thought and intention towards the gods. Like Hesiod, then, Xenophanes prescribes pious intent when carrying out a ritual. The Theognidean corpus, meanwhile, reveals a preoccupation with thoughts that do not match an individual's words or actions, and insists explicitly (as in lines 373–92) on Zeus's ability to see into a man's mind and heart (noos and thumos). This is a better piece of evidence in support of P. and P.’s thesis than the Hesiodic passage and one of the strongest in the book; however, they do not discuss 731–52, in which the poet chides Zeus for visiting punishment on the innocent who have inherited the guilt of their fathers for such deeds as perjury (that is, they are tainted by inherited agos).

Aeschylus and Sophocles are interested in cases where those with good intentions nevertheless find themselves in situations where they cannot avoid incurring agos (e.g. the dilemmas of Agamemnon and Orestes in the Oresteia, and Oedipus in Oedipus the King), yet P. and P. do not recognise these cases as a challenge to their thesis. Throughout Part 4, the section on drama, they reiterate that the tragedians portray impious and wrongful actions as the result of intentional agency, and they maintain that this mental activity (rather than words and actions) is the root cause of outrage to the gods and thus pollution. However, their main thesis requires a demonstration that an impious mind causes divine outrage even in the absence of external word or deed, whereas the majority of the material from tragedy points to impious words and deeds as the proximate causes of divine anger. Only in Euripides do we find a clear opposition between inner and outer purity (Hipp. 317), and the explicit proposition (Or. 1602–5) that mental states should count at least as much as outer (ritual) purity.

Part 5, ‘A Different Kind of Inner Purity’, deals with the Orphic gold tablets, arguing that, to the degree we can establish a consistent eschatological doctrine for Orphism, it involved the pursuit of a pure soul (kathara psuchê) and thus represented a departure from traditional Greek religion, which viewed the dead as polluted. There follows in the conclusion a summary of the ritual impact of inner impurity based on the authors presented, a valuable discussion of the ‘seats’ of inner impurity and how they differ by genre (the phrenes being most characteristic of tragedy, except for Euripides, who also considers the psuchê), and a comparison of this terminology with that used in epigraphic sources (all fourth-century or later). P. and P. argue that inner impurity is not to be viewed as a metaphor, but they do not distinguish between cases like that of Euripides’ Menelaus, whom Orestes accuses of having impure (i.e. villainous) intentions, and clear-cut cases of agos, where divinely-guaranteed norms have been broken. In the latter case, traditional Greek thought located the source of the pollution not in the mind of the afflicted person, but externally, in the anger of the offended deity or dead person.

Although I disagree with P. and P.’s conclusions, they offer an important corrective to those who would entirely divorce Greek ritual activity from a moral dimension. Just as theodicy was a concern for certain thinkers from Hesiod's time onwards, many poets and philosophers were also prescriptively occupied with the worshipper's mental state. This book provides a welcome addition to the growing body of scholarship on cognition, agency and emotion in Greek religion.