The principal purpose of Hegel’s philosophy of nature is not to reflect on the method and validity of the natural sciences, but to deepen our understanding of nature itself - to reveal what space, time and matter logically must be. None the less, Hegel does include in his phi
losophy of nature some brief remarks about the differences and relation between natural science and the philosophy of nature.
The most obvious difference between the two, he notes, is that natural science (or
‘physics’, as he sometimes calls it) proceeds from and is ultimately justified by empirical experience, whereas this is not the case with the philosophy of nature. A scientific theory is deemed to be true only if it is confirmed by observation or experiment. By contrast, a proposition in the speculative philosophy of nature is held to be true if it is derived logi
cally - by pure a priori reason - from the very nature of nature itself (and, ultimately, from pure indeterminate being).39
Hegel points out that science does not consist solely in gathering empirical information but also employs thought and understanding to classify objects, identify the causes of events and formulate universal laws of nature. In particular, he notes, science interprets the world around us in terms of certain (non-empirical) concepts - such as ‘force’ and ‘cause’
- and certain logical and mathematical principles which together constitute what he calls the ‘metaphysics* at the heart of science: ‘the diamond net into which everything is brought and thereby first made intelligible’40 Nevertheless, science draws on such concepts and prin
ciples in order to make sense of observed phenomena. The scientist’s aim is thus to discover the laws that best fit and explain the phenomena as they are currently known. In this sense, even though science is not a purely empirical and observational activity, it considers empir
ical observation to provide the ultimate warrant for its claims.
The relation between the philosophy of nature and empirical experience is somewhat more complicated. On the one hand, Hegel contends that the philosophy of nature ‘does not need experience’ because it derives the fundamental structures of nature a priori from the sheer externality of space. O n the other hand, however, Hegel insists that philosophy’s account of nature must ‘be in agreement with our empirical experience of nature’ and, indeed, that ‘the origin and formation of the Philosophy of Nature presupposes and is con
ditioned by empirical physics’.41 These two claims would appear to be incompatible. Let us consider how they might be reconciled.
Hegel recognizes that the philosophy of nature as such is an older discipline than natural science in the modern, post-Reformation sense, since it reaches as far back as Aristotle. Yet he maintains that modern science is the historical precondition of his own speculative philosophy of nature. As we saw in chapters 1 and 2, Hegel’s philosophy as a whole is the distinctive product of the modern world, especially of the modern claim to freedom that finds expression in Kant’s moral philosophy, the French Revolution and the modern
constitutional state. One of the other developments that made the modern world possible is the emergence in the sixteenth and seventeenth centuries of m odem experimental science: as Hegel puts it, human beings became ‘free through knowledge of nature’.42 Such science thus represents an essential historical presupposition of the development of Hegel’s freely self-determining speculative philosophy, including the philosophy of nature.
Hegel acknowledges, therefore, that his philosophy of nature is historically indebted to the great scientists of the past, such as Galileo, Kepler and Newton: for it is their empiri
cal discovery of the rationality in nature that paved the way for that philosophy to arise.
At the same time, however, Hegel insists that the philosophy of nature itself is a specula
tive discipline that derives the basic structure of nature wholly a priori - and independently of science - from the simple externality of space. Indeed, he maintains, philosophy is able to derive a priori some of the very laws of nature that science discovered empirically before the speculative philosophy of nature was conceived, including, for example, Galileo’s law of free fall and Keplers three laws of planetary motion.43 In this way, philosophy demon
strates its agreement with modern scientific experience. Philosophy secures this agreement, however, not by hosing its insights on scientific experience but by proving a priori that laws formulated by empirical science are truly objective; that is, by establishing the logical neces
sity of laws that science discovers empirically: ‘the Philosophy of N ature. . . has as its object the same universal [as science], b u t . . . it considers this universal in its own immanent necessity in accordance with the self-determination of the Concept’.44
Philosophy’s historical indebtedness to empirical science does not mean, therefore, that science and empirical experience constitute the structural foundation of philosophy. On the contrary, science makes it possible for a philosophy of nature to emerge that dem
onstrates its agreement with such science through pure reason alone. In this way, the apparent contradiction noted earlier is resolved: the philosophy of nature is historically dependent on, but structurally and logically independent of, empirical science at one and the same time:
the origin and formation of the Philosophy of Nature presupposes and is conditioned by empirical physics. However, the course of a science’s [i.e. philosophy’s] origin and the preliminaries of its con
struction are one thing, while the science itself is another. In the latter, the former can no longer appear as the foundation of the science; here the foundation must be the necessity of the Concept.45 There is also a further sense in which the philosophy of nature is (or may be) histori
cally dependent upon the development of science. The fact that one aspect of nature is made logically necessary by another does not mean that this will be immediately apparent to the philosopher. It may take a long time for the philosopher to see the logical connec
tion between the two, and it may even be the case, in certain circumstances, that the philosopher would not be able to see^the logical connection at all were it not for develop
ments in empirical science. In this latter case, the logical connection between the aspects o f nature in question would not itself depend upon the scientific discovery but would be wholly a priori The ability of the philosopher to recognize that a priori connection would, however, depend on the disclosures of science. Hegel’s ability to derive time, motion, matter, mass, free fall and solar systems logically from space does not, I think, depend on any specific scientific discoveries. In my judgement, however, he would not have been able to provide an a priori proof of Galileo’s law of free fall and of Kepler’s laws of planetary motion if those laws had not already been discovered by empirical science. In this respect, I agree with Buchdahl that Hegel did not claim that he could have discovered these laws by himself (in the way that he was able to deduce that time and motion are intrinsic to space).46
Hegel demonstrates a priori that such laws follow logically from the character of space, time, motion and matter, but he is able to do so only because they were first discovered
‘empirically by induction?7
Once again, therefore, we see that there is no contradiction in the idea that an a priori philosophy of nature is historically dependent on the deliverances of science. Indeed, it is not beyond the bounds of possibility that such dependence may extend into the future.
Further developments in empirical science could, perhaps, alert the philosopher to hith
erto unseen problems in his articulation of the logic of nature and require him to revise his account of that a priori logic (unless, of course, it is proven definitively that that logic is properly articulated already). Even if this were to occur, however, it would not mean that the logical structure of the philosophy of nature is itself founded on and determined by the current state of empirical evidence. That logical structure would still be determined by the immanent logic of nature, now correctly articulated. Science would simply have helped the philosopher to see more clearly precisely how that immanent a priori logic should unfold.
What has been said so far, however, is not quite the whole story, for there is a sense in which the philosophy of nature is dependent not only historically, but also structurally, on empirical science. Hegel makes it dear that, strictly speaking, the philosophy of nature does not derive a priori the empirical phenomena of nature themselves. What philosophy unfolds is a series of logical determinations or Begriffsbestimmungen. Such determinations incor
porate, but are not redudble to, the categories and concepts articulated in the Logic because they are the specific logical structures immanent in the externality of nature, rather than the sheer immediacy of being as such. To complete its account of nature, philosophy must then match these determinations - which have been generated by the distinctive logic of nature - with phenomena known through ‘representation’ ( Vorstellung), ‘intuition’ or sci
entific experience. Once this matching has taken place, philosophy can be said to have proven the logical necessity - albeit indirectly - of the empirical phenomena concerned.
Hegel summarizes his philosophical procedure as follows:
in the progress of philosophical knowledge, we must not only give an account of the object accord
ing to its conceptual determination [nach seiner Begriffsbestimmung], but we must also name the empir
ical appearance corresponding to it, and we must show that the appearance does, in fact, correspond to its Concept.48
Hegel daims, further, that if we were to make an error in identifying the empirical phe
nomenon that corresponds to a specific logical determination, this would not undermine the truth or validity of the logical determination itself. That determination would have been shown to belong necessarily to nature itself, and it would fall to us to look for the phenomenon that does actually correspond to it:
Our procedure consists in first fixing the thought demanded by the necessity of the Concept and then in asking how this thought appears in our ordinary ideas [ Vorstellung], The further requirement is that, in intuition, space [for example] shall correspond to the thought of pure self- externality. Even if we were mistaken in this, it would not affect the truth of our thought.49 This suggests that new scientific discoveries cannot invalidate a natural-logical determina
tion that has dearly been properly derived. If, therefore, an empirical phenomenon is ini
tially judged to correspond with a specific logical determination, but science later reveals that it does not actually do so, the thing to do, in Hegel’s view, is not automatically to
conceive the logical determination in a new way, but rather to associate the empirical phe
nomenon with a different determination (or consign it to contingency).50 This appears to be what happened to galvanism in Hegel’s philosophy of nature between 1817 and 1819:
Hegel’s conception of the logical structure of electrical and chemical relations does not alter significantly, but galvanism itself comes to be regarded as a chemical, rather than elec
trical phenomenon.51 Further advances in science could, of course, require other, similar changes to be made to the philosophy of nature. In this respect, Hegel’s a priori philoso
phy of nature proves to be open to new discoveries that science might make.
It has now become apparent that philosophy’s derivation of actual phenomena in nature, such as time, light and electricity - as opposed to its derivation of the natural-logical deter
minations to which those phenomena correspond - is not purely a priori, but requires the support of empirical science and experience. To the extent that a given phenomenon as described by science is correctly matched with a logical determination, then that phe
nomenon can, indeed, be said to have been shown a priori to be logically necessary. The logical derivation of such a phenomenon is, however, indirect and requires the assistance of science.
For Hegel, the philosophy of nature and empirical science are two distinct enterprises with different aims and they should not be confused with one another. Philosophy’s aim is to set out what is made logically necessary by the externality of nature itself. Its task is not to explain everything in nature, but to shed light on that limited range of natural phe
nomena that have their ground in nature’s own inherent logic rather than contingency.
Science, by contrast, seeks to discover as much as it can about all aspects of nature and its fundamental laws through a combination of mathematical reasoning and empirical inves
tigation. Philosophy and science do, however, complement one another in the following ways:
1 Philosophy complements science by demonstrating that certain phenomena described by science (and laws discovered by science) are not mere contingent givens but are made necessary logically by the very nature of nature itself (provided, of course, that the correct phenomena have been associated with each logical determination).
2 Science complements philosophy by (a) refining our empirical knowledge of the natural phenomena that philosophy associates with its logical determinations, (b) investigating the natural processes that produce such phenomena (processes that philosophy itself is not able fully to explain), (c) increasing our understanding of those phenomena that philosophy regards as ‘contingencies’ falling outside the scope of its comprehension, and (d) preparing the way historically for the philosophy of nature in two significant ways:
(i) through contributing to the modern consciousness of freedom, out of which self- determining, speculative philosophy grows, and (ii) through discovering certain laws of nature - such as Galileo’s law of free fall - whose logical necessity the philosopher then seeks to demonstrate. (As I noted above, the future progress of science could also alert philosophy to problems in its articulation of the logic of nature - though only if the philosopher has not been completely rigorous in the articulation of that logic in the first place.)
Philosophy and science are thus not regarded by Hegel as competing or mutually hostile disciplines. He does not consider modern empirical science to be incompatible with a priori philosophy of nature and so does not accept that the former has rendered the latter out
dated. Nor does he harbour any insidious (or foolish) intention of his own to replace
empirical science altogether with a purely rational philosophy of nature. On the contrary, he recognizes that the philosophy of nature needs to cooperate with the empirical sciences, and he firmly rejects ‘that humbug in natural philosophy which consists in philosophizing without wide knowledge’.52 Evidence of Hegel’s own commitment to such cooperation can be found in the long list of scientists on whose work he himself draws in the philosophy of nature, a list that includes among others Galileo, Kepler, Newton, Lagrange, Laplace, Herschel, Berthollet and Cuvier.
Hegel’s openness to changes and developments in science does not, however, mean that he regards science as being altogether beyond criticism. As we have seen, the philosophy of nature demonstrates (albeit indirectly) the logical necessity of certain phenomena and it also determines the true logical structure of those phenomena. If scientists put forward a conception of those phenomena that is utterly incompatible with the insights of the spe
culative philosophy of nature, then philosophy is entitled to ask those scientists to look again at their observations and at the interpretations they put upon them (assuming, of course, that philosophy itself has not made an error in its logical derivation). In Hegel’s view, therefore, the philosophy of nature does not have to accept without criticism what
ever science claims about nature, but it is able to discriminate between different scientific conceptions of the world and, if necessary, can even act - as Manfred Gies puts it - as a
‘corrective for natural sciences’.53 Philosophy assumes this role because, for it, ‘the Concept is the judge that decides what is the True’54 As we have seen, however, there are clear limits to what the Concept shows to be logically necessary. There are thus also clear limits to the extent to which philosophy is entitled to ‘correct’ science.
The idea that science might, under certain circumstances, be subject to such critical scrutiny or correction by the philosophy of nature is bound to make scientists uncom
fortable. Yet this right of philosophy follows from the fact that philosophy and science both describe the same world. If the philosophy of nature has to agree with what empirical science shows us about the world, it can expect such science in turn to acknowledge and accept what philosophy demonstrates to be true. One of the tasks facing students o f Hegel in the twenty-first century will thus be to determine whether post-Hegelian science - in particular, relativity theory and quantum mechanics - is able to meet this expectation or whether it requires correction’ in some way by the philosophy of nature. Conversely, of course, scientists interested in Hegel will want to know to what extent his philosophy of nature can itself accommodate the insights provided by these two powerful theories. Such an investigation, however, lies beyond the scope of this study (though there are brief remarks on the relation between Hegel and Einstein in the next chapter).
In my view, the most significant criticism levelled at science by the philosophy of nature is that science sometimes employs categories that are appropriate for one set of phenom
ena to understand other phenomena that call for more complex categories. Consider, for example, the relation between chemistry and life. Although science may show that chem
ical processes produce life, philosophy makes it clear that life has a formal structure that is not reducible to that of mere chemical relations (and that similarly the structure of chem
ical relations cannot be articulated in purely physical or mechanical terms). Philosophy, indeed, teaches us that each stage of nature ‘has its own proper category* (ihre eigentüm
liche Kategorie), which is ‘not also a category of a higher [stage] and is not to be carried over into the category of another stage’.55 In so doing, philosophy serves to remind science that it should not be reductive and conclude that, because life emerges out of chemical activity, it thereby consists in nothing more than such chemical activity. From the philo
sophical point of view, therefore, one of the tasks of natural science must be to explain how
natural processes can produce a new phenomenon with a distinctive character of its own that is not itself intelligible purely in terms of the processes that gave rise to it.
Hegel notes, however, that science has a tendency precisely to try to reduce one phe
nomenon to another in the search for a single universal explanation for things. He remarks that
physics looks on these universals as its triumph: one can say even that, unfortunately, it goes too for
physics looks on these universals as its triumph: one can say even that, unfortunately, it goes too for