13.1 What Is the Problem?

Of all the things he did, Hegel’s Naturphilosophie has had the most controversial and convoluted reception, indeed far more than anything else in Hegel’s works. As Cinzia Ferrini has shown in her authoritative history of its reception, outside of a very small acceptance in Hegel’s lifetime it was scorned in the nineteenth century as a botched job, perhaps a work of an incompetent in over his head, only to emerge much later on in the 1970s more or less as at least a competent engagement with figures in the history of science, and only from the 1980s onward as something itself of philosophical importance and as perhaps opening up entirely new avenues of research (Ferrini Reference Ferrini2014).Footnote ¹

Even the term itself, Naturphilosophie, proves to be problematical when one tries to translate it. Almost all people writing on it prefer the term “philosophy of nature.”Footnote ² However, earlier natural scientists, to use the later term, called themselves “natural philosophers,” a usage that Hegel at least somewhat approves.Footnote ³ Moreover, Hegel actually stresses the continuity of his Naturphilosophie with “natural philosophy” in statements such as: “In the first place, we find Naturphilosophie in a peculiar relationship to natural science in general, to physics, natural history, and physiology; it is itself physics, but rational physics” (Enc. 2, 2). Thus, I shall take Hegel’s Naturphilosophie to be his “natural philosophy,” a Wissenschaft (or “rigorous theory”) that he takes to have at least equal standing with the natural sciences.

How one interprets Hegel’s Naturphilosophie depends on how one interprets Hegel’s philosophy overall. Here I shall lay my cards on the table. I locate Hegel’s topic – why nature is a proper, even necessary topic for philosophy – within the background of a Kantian–Fichtean debate about the relation of logic to the world and to the possibility of an idealist “natural philosophy,” that is, by locating Hegel in what has come to be called a “post-Kantian” mode of interpretation. By this is meant very broadly seeing Hegel as responding to Kant’s philosophy by reworking the main themes of that philosophy to avoid what had come to seem to Hegel and his contemporaries as the unavoidable pitfalls in Kant’s own statements of his views. The goal of that kind of post-Kantianism is the production not simply of a slimmed down and more consistent Kantianism but something that takes Kant in directions he himself did not want to go but which follow from or are developments out of his central concerns and themes.

Part of the debate in the post-Kantian hothouse of the late eighteenth and early nineteenth century had to do with how to carry Kant forward without any reliance on what Kant himself had thought was completely necessary, namely, pure nonconceptual intuitions (of space and time) to provide content to otherwise empty but necessary self-conscious conceptual form. Almost everyone important in the debate agreed that there were no such things as pure nonconceptual intuitions but how to do without them was a matter of intense disagreement. In his own Science of Logic, characterized as a “thinking thinking about what it is to be thinking,” Hegel proposed that such pure thought can in fact generate new a priori content for itself so that Kant’s own worry about emptiness can be shunted to the side. As all readers of Hegel know, he employed a dialectical method in which apparent contradictions among what seem to be unconditionally valid concepts can – by the way in which thinking tries to stabilize itself in light of such contradictions (and to avoid what Kant called the threat of the euthanasia of reason that comes with such a procedure) – be driven on its own terms to develop new concepts that provide that stabilization.

To this end, Hegel developed a logic, a “pure thought” of “Being” (of individuals as qualitatively and quantitatively determined), a logic of “essence” (of structures that explain appearances of these individuals as having the shape they do), and then finally a logic of “concept” (or of “conceptuality” in general in which one looks at the overall formal and material inferential structure of thinking), capped off with an understanding of thought grasping that these are indeed the essential determinations of thought thinking about what is a priori necessary for thinking itself (i.e., as Hegel puts it, grasping the absolute Idea as the “method” behind all of this).Footnote ⁴

13.2 From Logic to Nature

However, the way in which Hegel describes the move from Logic to “natural philosophy” is and has always been seen as problematic. The move comes at the end of the Logic, where Hegel’s system goes from the pure Idea in the Logic to the Naturphilosophie – the pure “Idea” technically in Hegel’s regulated terminology is the unity of the concept and its objectivity or reality but, putting it a bit more colloquially, it is the expression of a comprehensive conception of agency and nature. Hegel’s description of the move, famous as it is, is worth stating relatively fully:

The pure thought of the Logic is free, that is, completely self-determining, and it now stands in relation to an other that is or is supposed to be no absolute other. However, if nature were something else besides or alongside the pure thought of the Logic, then the Logic itself would be, as Hegel would put it, only finite, and that would stand in contradiction to what he says about it.

How one makes sense of the passage from Logic to natural philosophy really depends on how one sees Hegel’s project as a whole (which should be itself a rather obviously Hegelian point). One possible interpretation of the passage, held by many for a long time, would quasi-theological: God (which some take to be the absolute Idea of the Logic) emanates the world from himself in the act of creation. Hegel does in fact at times use language that suggests that, but I take his use there to be metaphorical. Instead, I take Hegel to be saying something very generally along early Wittgensteinian lines: Logic is the form of the world, the basis of all intelligibility. But where do we go from there?

If nature were the pure externality of the self-enclosed thought of the Logic, then the natural philosophy that would follow would be that which follows a priori from the very thought of there being a sphere that is other than pure thinking.Footnote ⁵ Roughly put, that generation sees the concept of externality itself as already a concept that has been developed in the Logic, at first in the “Doctrine of Being,” so that the concept of externality is itself not external to the Logic, not something brought in from the outside. Hegel’s natural philosophy is thus an answer to the question: What is implied in pure thought’s concept of externality when applied to pure thought itself? At first, that concept is itself empty. It refers solely to what the pure thought of the Logic does not encompass, and it follows from the concept of “externality” that is itself already developed in the Logic.

Given that question, one possible answer obviously suggests itself, but it is not Hegel’s answer, and it would go like this. Outside of logical form, there is nothing more a priori to be said about externality. After stating the case about externality, the rest that comes after would be just empirical observation and empirically informed theory building. On that way of understanding it, since everything else would be an empirical matter, the “natural philosophy” following the Logic would turn out to be only a couple of pages long.

13.3 What Is Doing the Work of Explanation in Natural Philosophy?

But in fact, Hegel begins his natural philosophy with the categories of space and time since these are the pure forms of the thought of externality to pure thought. Space, he says, is “a mere form, i.e., an abstraction, that of immediate externality,” and he goes on to add that in intuition, space shall correspond to the thought of pure self-externality” (Enc. §254/Enc. 2, 29). Likewise, time is “the negative unity of self-externality” (Enc. §258/Enc. 2, 34). Hegel affirms the Kantian idea that space and time are forms of intuition but with a weighty proviso: They are forms of intuition only because they are also the forms of material things, so that, as Hegel puts it, in time “as in the case of space, the distinction of objectivity and a subjective consciousness confronting it, does not apply” (Enc. §258R/Enc. 2, 34). The thought of something external to the concepts of the pure Logic are the thoughts of space and time, and as the basis of the pure intelligibility of nature they are therefore not merely features of our contingent, subjective makeup. Just as the pure thought of, say, quantitative difference is identical to the reality of quantitative difference (since if it were not, there would be no intelligibility to such thought at all), the thought of space as the pure externality of pure thought is the thought of the reality of space.Footnote ⁶ And as the form of pure externality itself, space and time are to be thought of in terms of the categories of “quantity,” namely, geometry and mathematics, continuous and discrete magnitudes.

But, as Hegel puts it (which is a point to which we shall return), “nature is, in itself, a living whole” (Enc. §250/Enc. 2, 24), and described purely in terms of mathematical representation, nature would not be represented as the “living whole” it is supposed to be. In fact, if nature were completely the domain of a kind of absolute externality, it would be merely a concatenation of objects, each fully external in its determinateness to the other, and the study of nature would be that of noting and observing regularities and then giving them at best a mathematical form for purposes of prediction. If so, then nature as a whole would only be a grab-bag collection of things and regularities that would possess only as much unity as a particularly formed mathematical theory could give it.

In Hegel’s eyes, the very defect of that conception of nature lies not in the idea of a “mathematized” nature itself but in all the forms of overly strong commitments to empiricism as the appropriate and sole method for studying nature.Footnote ⁷ The regularities that empiricists find in nature are indeed real enough, they exist, but they are not, in Hegel’s rather technical distinction, actual, wirklich (or effectif, as the French render wirklich). Empiricism is not so much wrong as it is one-sided. Empiricism thinks that once it has established the empirical regularities and tied them into empirically based theories, it has explained why things are. However, the job of philosophy (as a kind of Hegelian logic-as-metaphysics) is first to determine the basic objects (or “totalities” as he also calls them) of nature, and by determining them, determine their intrinsic powers (Potenzen), and then by virtue of those powers investigate what those objects would do in terms of what would count as following from their nature. What is doing “the work” in nature are these basic “objects,” not the regularities. Or, as Hegel defines Wirklichkeit (almost always rendered as “actuality”), “What is actual can have an effect; something announces its actuality by what it produces” (“Was wirklich ist, kann wirken, seine Wirklichkeit gibt etwas kund durch das, was es hervorbringt”) (SL 482/WL GW 11: 385–86).Footnote ⁸ Or, as we might more succinctly put it: The actual is that which is really at work in reality.

These basic “objects” and their powers are to be established by developing them out of the concept of what is external to (logical) thought. Moreover, or so Hegel thinks, these basic “objects” not only have a nature or “essence” intrinsic to them, they also each stand to each other in a kind of a priori order such that the more elementary of them stand at a lower level of sorts to the more complex, and this ordering itself is also supposed to be a priori, not something discovered after the fact. Only grasped in that way can nature be comprehended as a whole, a unity, and not as the name for a diverse and perhaps incompatible grab-bag of states of affairs.

Hegel establishes this view near the beginning of the “natural philosophy” of the Encyclopaedia:

The empirical laws the natural scientist discovers are thus themselves to be explained in terms of the powers the natural philosopher establishes, where those powers express the object’s nature, and in the levels of such powers, each is a power of the other (as analogously four is a power of two squared).

13.4 The Unity of Nature?

Since nature as a whole would be the unity of these basic objects and not just a collection of empirically established events of various sorts, nor just a collection of empirically established regularities, the empirically discovered laws that govern those objects find their own limits in the limits of the “totality” in question, and natural philosophy would therefore be the derivation of what these objects must be and which objects there are, all in terms of what is necessary to think through the concept of externality to pure thought (i.e., external to the system presented in the Logic).

Although the goal of an idealist natural philosophy is to comprehend nature as a whole, which involves the generation of all the forms that would arise from externality to thought and thus incorporate all the ways in which at first discreteness and continuity take shape, and then later as the way in which process and product dialectically play off each other in the chemical object, and then on to a variety of other shapes that all embody the central tensions within nature conceived as a whole.Footnote ⁹ However, nature as a whole cannot itself be neatly grasped completely as a whole. Hegel says of nature that “[t]he contradiction of the Idea, arising from the fact that, as Nature, it is external to itself, is more precisely this: that on the one hand there is the necessity of its forms which is generated by the concept, and their rational determination in the organic totality; while on the other hand, there is their indifferent contingency and indeterminable irregularity.” He calls this (quite famously) the “impotence of nature,” nature’s inability to fully and completely organize itself intelligibly (Enc. §250/Enc. 2, 22–23).

The idea of the “impotence of nature” throws more light on what these “rational objects” are supposed to be. Although “natural philosophy” necessarily presents nature as an intelligible whole, not all of the necessary forms are realized in the way that the concepts of their domain would seem to indicate. Nature as a whole seems to embody what some have come to call generic universality that is not the universality of quantification (where one counterexample disproves the universalization) but that of a practice or form of life in which there can be many deviations from the universalization that simply count as something like defects, not as disproof of the generalization. (To take Michael Thompson’s now iconic example: The three-legged cat remains a cat even if a bit off the norm of feline nature [Thompson Reference Thompson2008, 203].) That however follows from Hegel’s conception of nature as a whole as something akin to an organic life-form, and although he is happy to take up the requirement, it is not clear that he has in fact established that organic view of nature or instead simply be led by it.Footnote ¹⁰ In any event, nature’s “impotence” is not merely a matter of contingency but of the lack of capacity on nature’s part to live up to its concept, of what it is “supposed” to be or do, and that depends on seeing nature as a whole as a life-form.

Even Hegel himself admits that in speaking of the world as an organic life-form, he is using “life” in an extended sense. For example, he says:

That seems to be saying that all forms of systematic organization of matter in nature (such as the solar system, one of Hegel’s prime examples) had to be taken as, as it were, unities on the way to life, so much so that the concept of “living” itself could be extended to them not as they really existed but only in terms of what kinds of possibilities were open to them (in their “in itself,” an sich existence). All systematically organized matter is on the way to life until it finally gets there. It does not follow from Hegel’s system that life was fated to emerge but rather that all it required was the right systematic ordering of matter. The systematic ordering in place was not within the purview of “natural philosophy” to discover, but rather was to be established by the empirical science of biology.

On Hegel’s view, instead of presenting itself as a pristine logical system, nature, as external to itself, is always dependent on something other than what it happens to be in order to be what it is, whose overall shape is clear and ordered but whose details, because of the “impotence of nature,” necessarily have to be muddy and checkered in parts. For Hegel himself, nature simply does not have, as it were, the power as a whole to live up to all its other powers, to be what it is supposed to be or at least what would follow from its being external to (logical) thought. That is the “impotence” of nature, which is not merely a function of its contingency.

Is that view of nature as a whole logically demanded by the very concept of “externality to (logical) thought”? I for one do not see it. It requires some extra premises to make that leap, such as when Hegel says in closing: “The aim of these lectures has been to give a picture of Nature in order to subdue this Proteus: to find in this externality only the mirror of ourselves, to see in Nature a free reflex of spirit: to know God, not in the contemplation of him as spirit, but in this his immediate existence” (Enc. §376/Enc. 2, 445). If that is the aim, then something like the view that nature as a whole exhibits something like the structure of a life-form would perhaps make some sense. But without that supposition, that view becomes considerably less compelling. If so, its externality to thought would result in a nonorganic view of nature as a whole, and accommodating that would force a major change in the Hegelian system as it stood in Hegel’s lifetime.Footnote ¹¹

The rational objects of Hegelian natural philosophy function more like paradigms for investigation (although not Kuhnian paradigms) but even more so as models to be used in guiding empirical investigation. The mechanical model, for example, which uses analytical geometry and calculus as its view of how things interact sets up a field of investigation (a “totality,” as Hegel would see it), and it is this totality which thus sets up Newton to be able to unify Galilean laws about falling bodies with Kepler’s laws of planetary motion. Newton could do this, so Hegel seems to say, because of the unity which is already present in the concept of the mechanical realm itself and which then only needs to be posited or rendered explicit. Each of Hegel’s “rational objects” of nature is such an ideal model, an unified field of investigation that defines the field’s powers and which in turn calls out for an empirical investigation of how these powers actually operate in the vast continuum of nature.

The ideal totalities of nature are, in Hegel’s account, what is doing the work in explaining the regularities of nature. These ideal wholes (the mechanical object, the chemical object, the living object, and so on) as each having a distinctive set of powers thus also each exercise a different form of causality. Mechanical causality, for example, is different from chemical causality. These wholes exercise a form of causality that is supposed to follow from thinking about what is external to pure thought, but as external, the specific causal laws falling under these ideal wholes have to be themselves empirically established. The causal power of the mechanical realm is explicated in the terms of the mathematics of physics, that is, the combination of otherwise mutually indifferent entities that are what they are outside of the wholes into which they are combined. The causality of the chemical realm has to do with the way in which different substantial individuals can combine with other such substantive individuals to make new substances with new and different powers than that of simply adding up the individual powers of the components. In such chemical causality, the product is determined by the process that creates it, and the process is what it is only in combining these matters. Which things combine with which has to do with locating the “elective affinities” (Wahlverwandtschaften) that hold between the entities. Finally, there is the area of biology – of life – where, as Hegel says, “the causal relation falls away, and generally in the sphere of life, all the categories of the Understanding cease to be valid” (Enc. §343/Enc. 2, 117). In life, to be sure, mechanical causality as well as chemical causality is present, but, as Hegel understood the matter, life involved more than just biomechanics and biochemistry: One had to understand the organism as a self-organizing whole, whose parts are functions, and where the parts become detached and identifiable apart from the organism, the organism becomes ill or dies. Hegel’s conception of biology was nonvitalist – he posited no special metaphysical force to explain life – but he did claim that the specific mode of organization of life’s elements was the crucial matter in accounting for life as a special “object” or totality in nature that was not exhausted by mechanical or chemical models of explanation.Footnote ¹² Hegel also noted (in a kind of “hedging his bets” way) that “the chemical process is thus an analogue of life,” to which he adds, “if the chemical process could carry itself on spontaneously, it would be life; this explains our tendency to see life in terms of chemistry” (Enc. §326Z/Enc. 2, 236).Footnote ¹³ The domain of “life” is that of the causality of self-organization and not that of mechanical causality or the “product-process” causality of chemistry.

This extends all the way to Geist, whose constitutive causal power would be that of freedom, which is a power other than all the other natural powers – in fact, it is so different from mechanical causality that it is easy to suppose that it must be a nonnatural power, but it is, at least in Hegel’s construction of nature, a firm feature of the natural world belonging to those set of creatures we call “the human” and of which the model is that of Geist taken as “self-conscious life.” It is not the language of mechanical causality, nor that of chemical causality, nor even just that of organic, holistic self-organization. It is instead that of manifestation, of expression, of the way, for example, a language shows itself in the activities of its speakers and the way in which the speakers manifest the language.Footnote ¹⁴ How that specific realm of nature develops, how it at first takes itself to be nonnatural, and how it comes back to a recognition and affirmation of its natural status as a matter of its own sociality is, however, another story for another place and time.Footnote ¹⁵

Hegel was also aware of the skepticism that many in the community of natural scientists of his day had toward this kind of philosophy since they were for the most part committed empiricists intent on studying regularities. However, he notes: “I have therefore set down here only the rudiments of a rational procedure in the comprehension of the mathematical and mechanical laws of Nature as this free realm of measures. This standpoint, I know, is ignored by professionals in the field; but a time will come when this science will require for its satisfaction the philosophical concept” (Enc. §270/Enc. 2, 82–83). Hegel’s optimism on that point has not exactly borne fruit.

13.5 From Logic to Nature (Again)

This brings us back to the issue with which we began, which asks what is the best way to make sense of the transition from the Logic to the Naturphilosophie and how does this help us to understand what was at stake in Hegel’s overall philosophy as a whole? The post-Kantian interpretation I have put forward here suggests the following. The Logic is the domain of pure thought, pure reason, and it sets the limits for making sense of making sense.Footnote ¹⁶ However, pure thought has no causal power on its own. It does not therefore form one of the basic models (i.e., Hegel’s rational objects) that demarcate what is doing the explanatory work in accounts of nature. Pure thought does indeed have the concept of causal power, but it lacks that power itself. This should not be surprising. Hegel himself speaks this way in a variety of places, but it comes more often to the fore in his practical philosophy, as for example when he says, rather forcefully, that “laws and principles have no immediate life or validity in themselves. The activity puts them into operation … has its source in the needs, impulses, inclinations and passions of man” (LPhWH-N 70). (However, unlike the Humean model, which sees pure thought and natural movement as two different spheres which have to be added on to each other at best, Hegel sees them – at least with regard to human action – as functional parts within a larger whole.)

On its own, the domain of pure thought is, Hegel says, a “realm of shadows” where the light source has to be that of the unity of nature and spirit coming together to provide the conceptual account of itself, an account which, as logic-metaphysics, is in fact the first book in the whole series in which it gives the final account.Footnote ¹⁷ It thus presents the image of “infinity” so central to Hegel. In finite matters, the image is that of a line or a series extending out to infinity such that no matter how far out one goes in the series, one always has further to go. Hegel calls this the bad infinite or the untrue infinite. The image of the good infinite, on the other hand, is that of the circle: If one begins at a point on the circle and starts traveling on the line from that, one will eventually come back to where one began, and one will do that infinitely if one keeps traveling. In that way, “thinking” has the infinite as its determination since it starts out empty, gets entangled in new content, and finally arrives back at the point at which it started in the circle. It also follows that to the extent that the circle and not the line is the guiding metaphor, in principle one can start anywhere in the system since one will always end up back there.

Thus, as Hegel somewhat enigmatically points out, the whole system of his kind of Wissenschaft is that of a “circle of circles,” in which no matter where one begins, one always arrives back at the same place if one travels long enough (SL 751–52/WL GW 12: 252). In another work, at the very end of the 1807 Phenomenology, Hegel misquotes some lines of poetry from Schiller to use a different metaphor to make essentially the same point: “Out of the chalice of this realm of spirits / Foams forth to him his infinity.” Instead of the Logic freely “releasing itself,” in the Phenomenology, absolute knowing, on its way to the system, “foams up” (schäumt) as this kind of infinity that emerges only out of the “conceptually grasped history” of self-conscious life – Geist – comprehending what it is and what ultimately matters to it (PS 467/PhG GW 433–34). The image of absolute spirit as merely reflecting on itself without that element of the “real” (in this case, conceptualized history, begriffne Geschichte) would only leave us with a picture of self-conscious life sitting on its throne “lifeless and alone,” whereas in the Logic, we have a metaphorical picture of pure thought coming to see itself as only a shadow seeking to become efficacious in more than its own self-enclosed, self-determining realm of thought thinking thought. In both cases, the point has to do with the self-enclosed nature of conceptual thought, its powerlessness to effect matters, and the logic of that relation of purely conceptual thought and “external to” purely conceptual thought. That image – of the necessity and self-enclosed nature of “pure thought” and the externality of the world without which it would be powerless – is at the heart of the dynamic of the Hegelian system.

13.6 Conclusion

The history of science has not exactly been kind to Hegel’s view of the a priori status of the basic models he proposed.Footnote ¹⁸ It has also long struck readers of Hegel that he might have done better if he had taken more of a view of “natural philosophy” as part of its own time grasped in thought and given it more of the treatment that the Phenomenology gave to other formations of self-conscious life (Geist) in terms of how it is that we have come to see certain modes of natural philosophy as necessary for us by virtue of the way in which past solutions have broken down and failed (in other words, if he had pursued a philosophical history of science instead of his own “natural philosophy”). In such a view, the unity of nature would be preserved, but space would be cleared out for a more dynamic idealist version of natural philosophy. We have a bit of a model for something like that in Ernst Cassirer’s Phenomenology of Knowledge (the third volume of his philosophy of symbolic forms) where he explicitly links his version of “phenomenology” to Hegel’s own (and not to Husserl’s version of) “phenomenology” (Cassirer Reference Cassirer1953). Looking at Cassirer’s attempt (and at those of his more recent admirers, such as Michael Friedman) might be a way of enriching the Hegelian proposals (Friedman Reference Friedman2001). That, however, would the topic of a very different chapter, which, as far as Hegelian circles that always initiate new circles goes, is exactly what one would expect.