I.

According to Kreines, Kant’s argument in the Transcendental Dialectic of Pure Reason can be summarized as follows:

Kreines’s Hegel accepts (E1) and (ANTINOMIES), but not (E2). He gives a different diagnosis of the antinomies, arguing that they arise from a dual demand for complete explainers that are sufficient reasons for a series of explananda, and bare substrata that underlie those explananda, while being indifferent to them (Kreines Reference Kreines2015: 166). (I will say more about this diagnosis shortly.)

Hence, Hegel’s view of the antinomies can be formulated in terms of the following revised argument (cf. Kreines Reference Kreines2015: 150f.):

On this reading, Hegel denies the epistemically pessimist conclusions that Kant wants to establish in his Dialectic argument. But at the same time, Hegel is still able to take the antinomies very seriously. In particular, he agrees with Kant’s contention that the antinomies are fatal for rationalist metaphysics, including metaphysical monism. For on Kreines’s reading, Hegel’s charge against the rationalist demand for a substrate rules out both Spinozism and all revised forms of metaphysical monism. Commenting on Hegel’s critique of Spinozism as vitiated by the demand for a substrate, Kreines writes: ‘Hegel’s concern cuts against the very idea of a One substance that is both something that everything is in, and also a sufficient reason for itself and for finite reality’ (Kreines Reference Kreines2015: 178). Hence, Hegel, on Kreines’s reading, also holds the following (labels and formulations are my own):

The approach to Kant’s Dialectic argument that Kreines ascribes to Hegel therefore directly rules out metaphysical monism. So in order to defend a metaphysically monistic reading of Hegel, I have to show that Hegel is actually not committed to the argument that Kreines attributes to him. I will focus on two points that I find problematic about this part of Kreines’s interpretation: the connection between metaphysical monism and rationalist metaphysics that he assumes (E4), and the diagnosis of the antinomies that he ascribes to Hegel (i.e., (DIAGNOSIS-HEGEL)).

Regarding (E4), I think that there are two straightforward ways in which this premise can be resisted. First, the idea that a substance is the bearer of properties that inhere in the substance is compatible with a range of various accounts of substancehood, and the view of substance as an indeterminate substratum is only one of those accounts. Therefore, there can be substance monism without the assumption of an indeterminate substratum. In particular, a substance monist can hold (as does Spinoza) that, first, all finite entities that we would describe as individuals are really properties that have one single substance as their bearer, or inhere in it; and second, that this substance explains the modes that inhere in it precisely in virtue of its determinate characteristics, namely, in virtue of its essence.

Second, a metaphysical monist can also deny that the relation between finite entities and the fundamental entity is correctly described, even in part, as a relation between a substance and its properties. Instead, it could be a relation of membership in a whole, or in a process, or a relation sui generis. So even if substance monism were necessarily committed to an account of substance as indeterminate substratum, a metaphysical monist could still resist (E4) by abandoning substance monism.

Hence, even if (DIAGNOSIS-HEGEL) is accepted, it does not follow that metaphysical monism is not a philosophical option for Hegel. In addition, I wish to argue that there are serious exegetical problems for the way Kreines understands Hegel’s views about the antinomies and the metaphysics of the understanding, too. As this part of Kreines’s reading is central to the overall argument of Reason in the World, and its interest is not limited to the particular question of whether Hegel was a metaphysical monist or not, I will address it in some more detail.

Let me summarize first Kreines’s account of the diagnosis that Hegel offers for the antinomies. According to Kreines, Hegel detects in rationalist metaphysics a general problem that is ultimately responsible for the antinomies. Since rationalist metaphysics is committed to the Principle of Sufficient Reason (PSR), the principle according to which there are no brute facts, it aims to identify complete reasons that explain why there is reality with its particular features. But at the same time, rationalist metaphysics makes, according to Kreines’s Hegel, the unwarranted assumption that reality conforms to the form of subject-predicate judgments (for short, SP-form) (Kreines Reference Kreines2015: 160). For Kreines, this is the reason why Hegel calls this form of metaphysics the ‘metaphysics of the understanding’, where understanding is, as in Kant, the faculty that is responsible for judgments (Kreines Reference Kreines2015: 165). As a consequence of the assumption that reality conforms to SP-form, rationalist metaphysics of the understanding interprets its ultimate explainers—God, the soul and the world—as final subjects. Such final subjects are ultimate bearers of predicates which are themselves indifferent with regard to these predicates. Hence, they are themselves indeterminate substrata, at least with regard to the predicates that they are supposed to support (Kreines Reference Kreines2015: 167).

According to Kreines, Hegel sees that a view on which complete explainers have to be final subjects is not a tenable one. For since final subjects are indifferent with regard to the predicates that they support, they cannot at the same time figure as explanations for those predicates: they lack any relevant determinate features in virtue of which they could explain those predicates. Kreines thinks that in Hegel’s eyes, Kant’s antinomies arise from two incompatible tasks that the objects of rationalist metaphysics (here: the world) are supposed to fulfil—the task of being sufficient reasons, and the task of being final subjects (Kreines Reference Kreines2015: 167). More concretely, Kreines’s Hegel analyses the antinomies as follows. The thesis postulates in each case an entity that satisfies the demand for a final subject. By contrast, the corresponding antithesis argues against such final subjects, on the basis that they cannot serve as sufficient reasons for the series of conditioned entities that they are supposed to explain (Kreines Reference Kreines2015: 173). On this diagnosis of the antinomies, the contradictions arise not because a legitimate conception of the unconditioned is applied to a subject-matter (viz., spatio-temporal objects) that it is not appropriate for; rather, the antinomies are the consequence of an illegitimate, incoherent way of understanding the notion of the unconditioned, namely, in terms of SP-form (Kreines Reference Kreines2015: 168). According to Kreines, this is the reason why Hegel claims that the antinomies are not restricted to the cosmological idea, but arise universally.

This is no doubt an ingenious account of Hegel’s take on the antinomies, but I think that it faces serious problems. To begin with, the antinomies arise, according to Kreines’s Hegel, because the completeness of reasons is understood in a way that combines two incompatible demands—that for final subjects, and that for complete explainers. But once it is acknowledged that these two demands are in conflict with each other, and that the first—the demand for final subjects—is unwarranted, the most natural reaction for an epistemically optimistic metaphysician would seem to be to simply abandon the quest for final subjects, and instead demand only complete explainers. Yet on the reading of the antinomies that Kreines ascribes to Hegel, this demand corresponds to the antithesis in each antinomy. Hence, we should expect Hegel to always drop the thesis, and keep the antithesis—to assume an infinite space-time, to deny ultimate simples, to deny causal spontaneity, and to deny an absolutely necessary being. Analogously, Hegel would have to opt for infinite series of conditioned entities in all other cases in which he would claim that antinomies arise. But this is neither something that one actually finds in Hegel, nor is it a consequence that Kreines could allow for; on his account, Hegel’s revision of what we should understand by a complete reason goes much further than that.

Further problems regarding this part of Kreines’s reading arise if we ask how precisely he can do justice to Hegel’s explicit discussions of the antinomies. To begin with, let us consider Hegel’s own remarks on how the antinomies should be resolved. In his most extensive discussion of the antinomies in the Second remark to the section ‘The pure quantity’ in the Science of Logic, Hegel writes:

By the ‘two determinations’, Hegel means the core notions that underlie the antinomies: simplicity vs. composition, spatiotemporal finitude vs. infinity, etc. Whatever Hegel means exactly when he says that the antinomies should be resolved by recognizing that the two opposites really belong to a ‘unity’ that constitutes one concept, it seems clear that this is quite different from saying that the antinomies can be resolved by merely abandoning the demand for final subjects.

Similarly, Hegel’s comments on the thesis and antithesis arguments themselves speak against Kreines’s reading. Hegel famously claims that these arguments are question-begging, and that the thesis and antithesis really are mere affirmations of the two opposed thought-determinations, as applied to the given subject-matter (e.g., SL: 5: 218). By contrast, it seems that Kreines has to regard both arguments as compelling—otherwise, it would be very easy to resist Kant’s Dialectic argument.

Last but not least, Kreines’s account is in tension with Hegel’s comments on how the antinomies are rooted in the shortcomings of the metaphysics of the understanding (for short, MU). This can be brought out by considering the account of MU that Hegel gives in §§26–36 of the Encyclopedia. In that section, Hegel characterizes the shortcomings of MU in terms of the following claims:

1. (1) MU employs ‘finite thought-determinations’, or it ‘dwells’ ‘in the still unresolved opposition’ (Enc.: §27, 8: 93).

2. (2) It contains the ‘mere perspective of the understanding’ on the ‘objects of reason’ (Enc.: §27, 8: 93).

3. (3) It takes the thought-determinations ‘in their abstraction’ as (a) ‘valid for themselves’, and (b) as ‘capable of being predicates of the true’ (Enc.: §28, 8: 94).

4. (4) It presupposes, without examination, that the Absolute can be cognized by attributing predicates to it (Enc.: §28 Rem., 8: 94).

5. (5) These predicates (or ‘determinations of the understanding’, §28) are ‘limited’ and mutually external and unrelated (Enc.: §29, 8: 96f.).

6. (6) MU presupposes soul, world and God as ‘readily given subjects’ (or ‘substrata’: 5: 61) from pictorial representation (Vorstellung) (Enc.: §30, 8: 97).

7. (7) For MU, such representations are the only standard for the adequacy of the predicates (Enc.: §30, 8: 97).

8. (8) Not only can these representations differ between individual thinkers; they are also indeterminate, and receive their determination from thought—as in a sentence, the subject is determined by the predicate (a reason why judgment is not an adequate form to capture truth) (Enc.: §31 with Rem., 8: 97f.).

9. (9) MU is dogmatic in that it presupposes the law of the excluded middle and the law of non-contradiction (Enc.: §32, 8: 98).

10. (10) In ontology, MU lacks a principle; it gathers up the ‘determinations of essence’ from representation and ordinary language, and only aims for a correct and complete description of linguistic usage (Enc.: §33, 8: 99f.).

11. (11) Rational psychology treats the soul as a thing (Enc.: §34, 8: 100).

12. (12) Rational cosmology deals with opposed characteristics of the world, and counts them as ‘absolute opposites’ (Enc.: §35 with Rem., 8: 101).

13. (13) Rational theology mainly deals with the question of which predicates match our pictorial representation of God (Enc.: §36 with Rem., 8: 103).

14. (14) Since rational theology treats the opposition of reality and negation as absolute, it has to view the concept of God as ‘the empty abstraction of the indeterminate essence, of pure reality or positivity’ (Enc.: §36 with Rem., 8: 103).

15. (15) Rational theology cannot give a satisfactory and determinate account of the relation between God and the finite world (Enc.: §36 with Rem., 8: 103f.).

As we have seen, Kreines thinks that Hegel’s central charge against MU is that it presupposes without argument a general conformity of reality with SP-form, a presupposition that leads to the demand for final subjects. Indeed, Hegel clearly states here that the shortcomings of MU have something to do with SP-form (claims 4 and 8); and at least for the case of God, he also refers to the idea of an indeterminate substrate (claim 14). But whereas I agree with Kreines that worries about SP-form play an important role in Hegel’s account and critique of MU, I think that upon closer inspection of his exposition of MU in the Encyclopedia, it becomes clear that what precisely he finds problematic is not that SP-form leads to the idea of an indeterminate substratum, but rather a quite different point.

Consider, to begin with, claim 14, in which the rationalist God is explicitly characterized as indeterminate. On Kreines’s reading, one would have to expect that Hegel presents this characterization as a direct consequence of the application of SP-form to God (claim 4). But this is not what we find in the text. Rather, Hegel treats the view of God as indeterminate as a consequence of quite another aspect of MU: namely, its interpretation of reality (or perfection) and negation as absolute opposites. The underlying reasoning can best be understood as follows. If reality and negation are absolute opposites, it follows that in order for a property to count as a reality, it needs to be entirely free from negation or imperfection. At the same time, God is defined by rational theology as the ens realissimum, so God’s properties must be pure realities. As a consequence, God’s properties must be free from negation or imperfection. Yet following Spinoza, Hegel holds that determinate properties as such necessarily involve negation. It follows that God cannot have determinate properties.

Not only does this line of thought not rely on the idea that MU in general asks for indeterminate substrata, but it also explicitly treats quite another assumption as the central error of MU: namely, the assumption that thought-determinations such as reality and negation are ‘absolute opposites’.Footnote ⁵ Indeed, Hegel elsewhere identifies this claim as the fundamental tenet of MU: according to him, MU expresses the viewpoint of the ‘abstracting and therefore separating understanding that persists in its separations’ (SL: 5: 38). Hence, MU denies that such thought-determinations as reality and negation can be intrinsically related to each other, and form moments of overarching logical structures. This characteristic of the understanding can be called its atomism. In the above list of claims, the charge of atomism can be seen as being expressed in Hegel’s talk about the ‘finite’ or ‘limited’ character of the categories of understanding (claims 1, 3, 5), as well as in his remark that rational cosmology deals with opposite characteristics of the world (claim 12). (Given the passage I have quoted from SL: 5: 38, claim 2, too, can be read in this sense.)

If atomism is seen as the central commitment that Hegel ascribes to MU, his remarks on the role that SP-form plays in MU can be understood as a further variation on the topic of atomism. For a natural corollary to the atomism of MU is the view that metaphysical cognition proceeds by ascribing predicates to objects like God, soul and world (claim 4), where the resulting metaphysical judgments obey the law of the excluded middle and the law of non-contradiction (claim 9). If, for instance, infinity is predicated of God, it directly follows that the opposite judgment ‘God is finite’ must be wrong. But this precludes from the outset the possibility that categories like infinity and finitude are intrinsically related, and that everything that is truly infinite also has to assume a dimension of finitude.

If, furthermore, atomism is wrong (as Hegel wants to argueFootnote ⁶ ), and metaphysical categories typically form complex logical structures that combine apparently opposed categories such as reality and negation or infinity and finitude, we should precisely expect that the understanding is confronted with antinomies. On this account, each side in an antinomy isolates one category (e.g., infinity) from its intrinsic connection to another category (e.g., finitude), and there is a valid argument for applying each of the resulting opposed categories to the objects of reason. The correct way to resolve the antinomies will then be to reconstruct the overarching logical structure that holds the apparently opposed categories together (for instance, by developing a philosophical account of infinity on which the truly infinite essentially involves a finite dimension). Thus, reading Hegel’s account of MU in terms of atomism also yields a way of understanding Hegel’s view of the antinomies which fits well with the passages about the antinomies that I have cited earlier, and avoids the problems that I have pointed out before for Kreines’s reading.

So far, I have argued that the reading of Hegel’s account of MU in terms of atomism can deal better than Kreines’s with what Hegel has to say about the indeterminacy of the rationalist God in claim 14, and with Hegel’s remarks on the antinomies. In addition, there is a further reason to prefer this reading to Kreines’s: while his interpretation can make sense of claims 2, 4, 8, 11 and 15 in Hegel’s account of MU, it is quite unclear how he can accommodate the rest of what Hegel has to say about MU. By contrast, it can be argued that all of the claims that Hegel ascribes to MU can be seen as being either expressions or consequences of atomism. I have already shown this for claims 1–5, 8, 9, 12 and 14, and now briefly turn to the remaining claims of MU.

If we see different thought-determinations as thoroughly unrelated, we are not able to cognize metaphysical subject-matters in a way that grasps their various aspects and features as mutually related, and as being explainable on the basis of the concept of the subject-matter. Rationalist theories consist in a series of formal derivations from a set of basic SP-judgments about the subject-matter, such as the metaphysical definitions and axioms in Spinoza and Wolff. Since rationalist metaphysics is ex hypothesi unable to take into account any intrinsic relations between metaphysical categories that might allow, in Hegel’s eyes, to derive such judgments and definitions from the concept of the subject-matter, it merely can treat such judgments as self-evident truths. But to the degree to which such judgments seem self-evident, they are so because the predicate correctly captures a feature of our ordinary notion, or ‘(pictorial) representation’, of the entity that the subject-term denotes—in particular, of God, the soul, and the world. This is why Hegel can claim that rational metaphysics takes as its ultimate standard of metaphysical adequacy our ordinary pictorial representations and our linguistic usage (claims 6–8, 10, 13). (For analogous reasons, MU is unable to explain the various features of a subject-matter on the basis of its concept. As a consequence, it cannot give an adequate explanatory account of the relation between God and finite reality (claim 15). At the same time, the reliance of MU on pictorial representations—which, according to Hegel, typically involve spatiotemporal imagery—leads to inadequate ‘reifying’ accounts of the subject-matters of MU, as Hegel points out regarding the soul in claim 11.)

It is true that Hegel characterizes the pictorial representations that MU relies on as ‘indeterminate’, and as ‘substrata’ (claims 6, 8). But on the reading that I have summarily sketched, they cannot be indeterminate substrata in the sense that Kreines has in mind. For if these pictorial representations are identical with our ordinary notions of God etc., and are to serve as the standard by which MU de facto evaluates metaphysical judgments, then they cannot be indeterminate in the sense of being devoid of properties or predicates. Rather, they are indeterminate in the sense of lacking clear, explicit conceptual content. On this view, metaphysical definitions make explicit what is implicit in our ordinary metaphysical notions. This requires that these notions are not indeterminate in the sense of being devoid of properties or predicates, but do have a content which is then made explicit in terms of metaphysical predicates.

I therefore conclude that Kreines’s account of Hegel’s diagnosis of the antinomies and his interpretation of MU is not sufficiently supported by Hegel’s text, and that an alternative reading in terms of atomism should be preferred. If this critique is sound, it follows that, in the above Hegelian argument, the premise (DIAGNOSIS-HEGEL) is not really held by Hegel. As a consequence, there is no warrant to ascribe to Hegel the rejection of metaphysical monism that results from the argument, even if it is accepted (despite the above worries) that Hegel is committed to the further premise (E4).

II.

In addition to the revised version of Kant’s Dialectic argument that he ascribes to Hegel, Kreines gives several further reasons for resisting a metaphysically monistic reading. I shall address these reasons in the remainder of my comments.

First, Kreines argues that Hegel’s alternative view of complete explanations not only abandons the demand for final subjects. It also rejects the idea that completeness of reason is a matter of there being something that does not depend on anything else, while other things depend on it (a ‘turtle with a jetpack’, in Kreines’s metaphor). Instead, completeness of reason is, on Hegel’s alternative view, a matter of an objective ‘concept or kind’, like that of spirit or freedom, ‘possessing explanatory import of its own’ (Kreines Reference Kreines2015: 217). As a consequence, Hegel grants explanatory completeness and metaphysical priority to entities—namely, spiritual beings—that do not possess priority in terms of dependence. Rather, Kreines points out, ‘the only dependence relation goes the other way: the complete form of reason is a process or movement that depends for its realization on the otherwise indifferent existence of incomplete forms of reason, as realizers’ (Kreines Reference Kreines2015: 232), i.e., on mechanical, chemical and organic forms of nature. Hence, Hegel would reject metaphysical foundationalism—the view ‘on which there is something … that depends on nothing while being the reason for itself and for everything real’ (Kreines Reference Kreines2015: 5). Instead, Hegel claims, according to Kreines, that ‘the end (something dependent) is first (in metaphysical priority)’ (Kreines Reference Kreines2015: 259). This does not seem to leave room for metaphysical monism.

I am not entirely sure how Hegel’s rejection of metaphysical foundationalism is precisely motivated on Kreines’s reading. Sometimes, Kreines claims that Hegel quite generally severs explanatory relations from dependence relations. Thus, he writes that for Hegel, ‘we should not understand reason in terms of dependence in the first place’ (Kreines Reference Kreines2015: 230). But this does not seem to be a necessary consequence of rejecting the demand for substrata. For from the fact that A is explained by B because A depends on B, it does not follow that B is an indeterminate substratum. Nor do I see how the alternative account that Kreines ascribes to Hegel could be spelt out without saying something about the way in which the properties of an instance of an objective kind depend on facts about that kind.

In other places, Kreines seems to hold a weaker view on which Hegel does not sever the link between explanation and dependence, but merely abandons the idea that complete explanations have to involve an unexplained explainer, or a ‘turtle with a jetpack’. Hegel’s reason for this is, according to Kreines (Kreines Reference Kreines2015: 205ff., 215f.), the view that the various forms of Hegel’s idea—and thus, the privileged forms of reasons in the world—are kind-dependent processes which essentially take place in something else, in a realizer which is not itself an instance of the kind that governs the process. I entirely agree that Hegel holds this view. But I do not think that it follows from this view that complete reasons cannot be turtles with jetpacks. The realization of a process may depend on a realizer, but it still could be the case that the realizer itself exists only because it is a necessary means or presupposition for the realization of the process. Indeed, in discussing teleological arguments for God’s existence in the Lectures on the Philosophy of Religion, Hegel explicitly distinguishes two cases of teleological processes. First, in ordinary teleological processes, purposes have ‘the power to realize themselves, but not the power to posit the means’ (VPR: 17: 35) for their realization—this is the case, for instance, with organisms, which need inorganic means in order to realize their internal purposes (VPR: 17: 34). But second, Hegel also acknowledges the possibility of teleological processes where the purpose also has the power to produce the means for its realization (VPR: 17: 35f.). This could provide the relevant form of teleology for a teleological form of metaphysical monism, according to which the one entity that fundamentally exists is an overarching teleological process.Footnote ⁷ In this case, the existence of natural realizers would be a necessary condition for the realization of the overarching purpose, and so the latter would depend on the former. But at the same time, the reason why there actually is nature could be that the concept of the overarching purpose—the logical structure of the absolute idea—entails that this purpose becomes realized, which, of course, would in its turn necessitate the existence of the necessary means for the realization of that purpose. In that case, the existence of nature would itself ultimately depend on the overarching purpose.

So I am not convinced that there is reason to attribute to Hegel a view on which consideration of the very notion of explanation, or of completeness of explanation, leads to a rejection of metaphysical foundationalism—neither on the stronger nor on the weaker reading of such a view.

Second, Kreines argues that a Hegelian metaphysical monism would either have to rely on an explanatory inference, or on an ontological argument (Kreines Reference Kreines2015: 263). Regarding the explanatory inference, he argues that according to Kant’s Dialectic argument, such inferences will always presuppose PSR. But Hegel’s metaphysics is incompatible with PSR, not least because Hegel assumes a massive incompleteness of possible explanations especially at the lower levels of reality. Similarly, Kreines thinks that Hegel’s assumption of such explanatory incompleteness is incompatible with ontological arguments, too. As he points out, this assumption entails that God’s power to determine finite reality is limited. Yet this, in its turn, excludes the kind of conception of God—e.g., as the most powerful being that can be thought of—that would be needed for an ontological argument (Kreines Reference Kreines2015: 263).

While I agree that Hegel rejects the PSR, I do think that Hegel holds a version of the ontological argument, and that this is entirely compatible with his view that there are brute facts. There are several passages in which Hegel endorses the view that God’s existence follows from his concept (e.g., SL: 6: 402, VPR: 17: 205ff., 529), and defends the view against Kant’s objections (e.g., SL: 5: 88ff., SL: 6: 402ff.). At the same time, Hegel can be plausibly read as holding the view that the realization of the absolute idea necessarily has to involve contingent and therefore brute facts—precisely because it requires an indifferent realizer, as Kreines had argued (see also Knappik Reference Knappik2013: 205ff.). Far from being a limitation of God’s (or the absolute idea’s) power, the existence of brute facts is, on this view, a necessary aspect of his self-manifestation in finite reality.

In addition to these objections, there is a further challenge that Kreines’s reading presents to metaphysically monistic interpretations of Hegel. Whereas the existence of brute facts as such is, as I have argued, compatible with metaphysical monism, the precise account that Kreines gives of the limits of possible explanations in Hegel leaves actually little space for metaphysical monism. For on the one hand, Hegel thinks, according to Kreines, that satisfactory explanations have to be based on immanent concepts—I fully agree with this. But on the other hand, Kreines’s Hegel holds that all such concepts or kinds in nature are simply there—there is ‘nothing to explain why there are multiple interconnected lawful kinds’ in nature, and ‘even life contains nothing to explain why there should be multiple species, and which there should be’ (Kreines Reference Kreines2015: 226). If this were Hegel’s view, the existence and properties of individuals in nature would be explained in terms of their place in a causal history and the fact that they instantiate determinate objective concepts or kinds; but neither the causal history nor the fact that these determinate concepts are instantiated would itself be open to an explanation. In that case, there would not be any room left for the idea that the fundamental entity of metaphysical monism plays any explanatory role with respect to nature, and this would stand at least in a strong tension with the spirit of metaphysical monism.

Still, I believe that the metaphysical reading can resist this challenge, too, for there is clear evidence to the effect that Hegel is actually much more optimistic about the availability of explanations even in nature than Kreines admits. Perhaps the most striking case is Hegel’s account of the mechanical laws. In the Philosophy of Nature, Hegel explicitly attempts to give for Galileo’s law of free fall a ‘proof of the law’ ‘from the concept of the subject-matter’ (Enc.: §267 Rem., 9: 78), namely, finite matter.Footnote ⁸ And in the Science of Logic, Hegel writes, in a passage that is worth being quoted at full length:

It is crucial to appreciate that Hegel not only claims here that mechanical laws are based on the immanent concepts of space and time which make up the concept of (mechanical) matter. He also makes the much stronger claim that there is a way to explain why space and time come with the determinate mechanical laws that actually govern the physical world: these laws can be derived, according to Hegel, from the very concepts of space and time. It follows that Hegel actually does think that the fact that immanent concepts such as matter come with determinate laws can be explained: at least for the case of mechanism, the fact that matter is governed by such laws can be explained in virtue of the fact that the concept of matter is itself based on the concepts of space and time. Mechanism is governed by Galileo’s and Kepler’s laws because it is of the essence of mechanism to be located in space and time.

Needless to say, Hegel’s claims about concept-based demonstrations of laws are utterly implausible. But what matters for our purpose is that Hegel explicitly advances explanatory ambitions which show that he takes nature to be explainable to an extent that Kreines does not allow for. In its turn, this explanatory optimism is based on a form of explanation that Kreines does not consider: an explanation in which the explanandum is a fact about one immanent concept—for instance, the fact that instances of matter obey mechanical laws—and the explanans is a relation between this concept and more fundamental concepts, here space and time. I think that the example of mechanical laws sheds much light on the general procedure and explanatory ambitions of Hegel’s Realphilosophie. For in addressing mechanism in the Philosophy of Nature, Hegel precisely argues that the more fundamental objective concepts of space and time are realized in the more concrete concepts of motion and matter (Enc.: §261, 9: 56ff.). This strongly suggests that the very way in which the Realphilosophie proceeds from one category to another has to be understood in terms of an explanatory project that draws on explanatory relations between different objective concepts. Of course, Hegel also warns that there are limits to this project: in particular, he emphasizes that there is no way to explain the specification of organic nature into determinate biological kinds (e.g., Enc.: §250 with Rem., 9: 34ff.). But even in this case, Hegel seems to assume that there is a way to give concept-based explanations for some divisions between objective kinds—at least the division into plants and animals, together with the basic features of these kinds (Enc.: §§343ff., 9: 371ff.).

I therefore conclude that Hegel is, pace Kreines, very optimistic with regard to the possibility of explanations for the fundamental structure of reality—its division into basic kinds, and their characteristics. In particular, his views about explanation are fully compatible with a version of metaphysical monism on which the fundamental structure of reality is necessitated by one explanatory principle, and everything else is partly made necessary, and partly at least possible, by this fundamental structure.