Immanuel Kant

Immanuel Kant (1724–1804) was a German philosopher whose work touched medicine on multiple sides. His moral philosophy — above all the principle that persons must never be treated merely as means but always also as ends — became the seed of modern medical ethics and the principle of respect for autonomy. His theory of knowledge asked which ideas are genuinely constitutive of nature and which are only regulators of thought, a distinction that shaped how biologists handled teleological concepts in living beings. His third great work, the Critique of Judgment, directly addressed the organism as a distinctive kind of natural thing. Later thinkers including Hans Driesch, Georges Canguilhem, Henri Bergson, and eventually Beauchamp and Childress all built on or explicitly argued with Kant’s positions, making him an unavoidable reference point in the philosophy of medicine.

Kant and Medical Ethics

The formulation most cited in biomedical ethics comes from Kant’s Groundwork of the Metaphysics of Morals: “Act so that you treat humanity, whether in your own person or in that of another, always as an end and never as a means only.”(Tom L. Beauchamp, James F. Childress, 2013) This is Kant’s second formulation of the categorical imperative.(Tom L. Beauchamp, James F. Childress, 2013) The first formulation requires that one act only on a maxim one could will to become universal law.(Tom L. Beauchamp, James F. Childress, 2013)

Kant’s categorical imperative has two key formulations: (1) act only on a maxim you can will to be universal law, and (2) treat every person as an end and never merely as a means.(Tom L. Beauchamp, James F. Childress, 2013) The second formulation is widely cited in biomedical ethics and is far more influential in this field than the first.(Tom L. Beauchamp, James F. Childress, 2013)

The second theory of moral status grounds it in cognitive properties such as self-consciousness, freedom, rationality, and capacity to give reasons; this supplies a sufficient but not necessary condition.(Tom L. Beauchamp, James F. Childress, 2013) The third theory grounds moral status in the capacity for moral agency (making moral judgments and having morally assessable motives); this is a sufficient but not necessary condition.(Tom L. Beauchamp, James F. Childress, 2013)

Kantian theory is praised in biomedical ethics for specifying categorical prohibitions — for example, against the deception of patients, against using research subjects as mere instruments — that utilitarian calculus could in principle override.(Tom L. Beauchamp, James F. Childress, 2013) Beauchamp and Childress use a kidney-donation case to show how a Kantian analysis asks whether the physician’s deception can be universalized as a morally acceptable practice, whereas a utilitarian focuses on probable aggregate outcomes.(Tom L. Beauchamp, James F. Childress, 2013)

Kantian ethics also faces persistent criticism. Beauchamp and Childress note that Kantian theory is poorly equipped to handle conflicting obligations, and that it overemphasises law-like rules at the expense of the moral significance of relationships, sympathy, and emotion.(Tom L. Beauchamp, James F. Childress, 2013) It is, they observe, “better suited for relationships among strangers than for relationships among friends or other intimates.”(Tom L. Beauchamp, James F. Childress, 2013)

Within virtue ethics frameworks, Kant appears as a foil rather than a resource. Pellegrino and Thomasma note that the shift away from character-based ethics in the postmedieval period was driven partly by Kantian deontology, which moved emphasis from the agent to the act and to principles.(Pellegrino, 1993) William Frankena’s well-known parody — “principles without traits are impotent, traits without principles are blind” — is itself a parody of Kant’s claim about intuitions and concepts, and is used by Pellegrino and Thomasma to argue that virtue and principle must work together.(Pellegrino, 1993)

Teleology and the Life Sciences

Kant’s Critique of Judgment (1790) is the point of departure for nearly all subsequent philosophical discussions of teleology in biology. Hans Driesch, writing in 1914, devoted a substantial section of his History and Theory of Vitalism to examining Kant’s contribution.

Driesch begins with a corrective observation: the primary object of the Critique of Judgment was not biological. Its goal, he argues, was ethical — to reconcile the world of nature and the world of human freedom so that moral activity could gain influence over the natural world. This ethical purpose, Driesch suggests, explains much of the obscurity in Kant’s treatment of biological questions.(Driesch, 1914)

The central Kantian contribution to biological philosophy is the characterisation of the organism as a “natural purpose”: for a thing to be a natural purpose, its parts must be possible only in relation to the whole, and the parts must be reciprocally cause and effect of one another’s form.(Driesch, 1914) Kant formulated teleological judgment as a regulative principle — a guide to inquiry — not a constitutive principle that establishes actual laws of nature. To treat teleology as constitutive would mean, in Kant’s words, “introducing into natural science a new causality which we borrow from ourselves alone, and yet attribute to other beings.”(Driesch, 1914) This distinction between regulative and constitutive principles is one of Kant’s most consequential methodological contributions to natural science.

The organism, for Kant, is distinguishable from any machine: a machine has motor force but not formative energy capable of transmitting itself to external matter and propagating itself. In a machine no part is produced by another part, nor is the whole produced by another whole of the same species — there is no “watch-making watch.”(Canguilhem, Georges, 1952/2008) Canguilhem, citing this passage from the Critique of Judgment, argues it anticipates the modern concept of self-organisation: the organism self-produces and self-reproduces in ways no machine can. Driesch presses the implication further: Kant writes that organized nature is not merely an “analogon of art” but rather an “analogon of life” — because the organism has formative power while a machine has only moving power. This passage, Driesch argues, should be read in a vitalistic sense, but Kant undercuts it with his simultaneous insistence that all matter is lifeless and that all physics must be resolved into processes of motion.(Driesch, 1914)

Kant also famously claimed that “no Newton can ever appear who will explain the production of so much as a blade of grass by laws of nature which no purpose has ordered.”(Driesch, 1914) Driesch reads this as expressing both Kant’s commitment to mechanism as an ideal of natural science and his acknowledgment that organisms resist fully mechanical explanation. Driesch draws out the tension: Kant simultaneously endorsed Blumenbach’s vitalism (the Bildungstrieb or formative impulse) and misread Blumenbach in the direction of a static teleology based on “original organisation.”(Driesch, 1914)

Driesch’s final assessment divides Kant’s vitalism: “In the case of man and his actions Kant is indubitably a Vitalist, while as regards the facts of organisation he is only problematically so.”(Driesch, 1914) Kant held two notions of causality simultaneously — a broad one compatible with vital autonomy (“all that happens presupposes something on which it follows according to a law”) and a narrower mechanistic one aligned with Newtonian physics — and was, Driesch argues, never clearly conscious of the logical distinction between them.(Driesch, 1914)

Driesch also uses his tripartite taxonomy of descriptive, static, and dynamic teleology as a “critical reagent” specifically designed to reveal ambiguities in Kant and Claude Bernard — thinkers who spoke of purposiveness but left unclear whether they meant a purposiveness grounded in mechanical structure (static teleology) or one arising from an autonomous vital principle (dynamic teleology).(Driesch, 1914) He concludes that virtually any biological view could find material to support it in the Critique of Judgment, and warns that biologists who appeal to Kant — for or against vitalism — should proceed with circumspection.(Driesch, 1914)

Edouard von Hartmann’s theory is historically important for vitalism as the first precise application of the doctrine of life’s autonomy to relate elementary life-factors to inorganic factors, and he treated “finality” as a pure category alongside substance and causality.(Driesch, 1914)

Emil du Bois-Reymond’s 1848 introduction refutes vitalism by asserting that life-force operations reduce to central forces of particles, but he is criticized for not actually carrying out that analysis.(Driesch, 1914)

Epistemological Influence on Philosophy of Medicine

Bergson’s Creative Evolution (1911) engages Kant’s epistemology at precisely the point where it bears most directly on biology: the relationship between the structure of the intellect and the structure of the world the intellect encounters. Bergson argues that there are three positions one might take on why mathematical physics works so well — matter determines the form of intellect, intellect imposes its form on matter, or they are regulated by a pre-established harmony — and that his own account of reciprocal co-origination from a single inversion of the same movement constitutes a fourth alternative to Kant’s three options.(Bergson, 1911) Bergson’s criticism of Kantian epistemology is that it generates a merely relative knowledge of nature, whereas physics, properly understood, touches the absolute within its domain. Bergson grants Kant that the cinematographic mechanism of thought — extracting immobile snapshots from moving reality — distorts our grasp of living processes, but contests the Kantian conclusion that we are therefore confined to appearances.

Canguilhem, writing in his essay “Knowledge and the Living” collected in A Vital Rationalist, identifies a persistent philosophical tension between concepts and life that runs through Aristotelian logic, empiricist nominalism, and Kantian transcendental philosophy alike, and argues that knowledge of life requires regulative ideas rather than deterministic causal frameworks.(Canguilhem, 1994)

The influence was also negative, as a counterexample. Broussais, the French physiologist who founded physiological medicine in the 1820s–1830s, regarded what he called the “Kanto-Platonicians” — Kant’s followers as filtered through Victor Cousin’s French spiritualism — as the chief intellectual enemy threatening to corrupt French medicine with ontological metaphysics. Broussais held that the metaphysicians of Germany had “disfigured the nature of man” by returning to Platonic notions rather than advancing on the empirical gains of Cabanis.(Broussais, 1831) This polemic illustrates how Kantian thought, even when filtered and distorted, became a live reference in early nineteenth-century medical debates about the appropriate basis for a science of the body.

Legacy in Philosophy of Medicine

Kant’s legacy in philosophy of medicine is present in at least three distinct channels.

First, through biomedical ethics. The principle of respect for autonomy as formulated in the Beauchamp and Childress framework draws on the Kantian tradition of treating rational agency as the ground of moral status and moral obligation. The canonical four principles of principlism are not themselves Kantian, and Beauchamp and Childress explicitly resist grounding their framework in any single moral theory.(Tom L. Beauchamp, James F. Childress, 2013) But the emphasis on autonomy, on treating persons as ends, and on categorical prohibitions against deception and coercion all carry the trace of Kantian moral philosophy.

Second, through philosophy of biology. The Critique of Judgment set the terms within which every subsequent discussion of teleology in living beings had to operate. The distinction between regulative and constitutive teleology gave biologists a philosophical vocabulary for speaking of purpose without committing to a metaphysical vital force. Driesch’s neovitalism, Canguilhem’s normative biology, and debates about whether natural selection is genuinely teleological or only analogically so — all trace in part back to Kant’s framing of the problem.

Third, through the broader epistemology of medicine. Kant’s account of what the intellect can know — and what exceeds its categories — shaped how philosophers of medicine thought about the limits of mechanistic explanation. Whether the organism can be exhaustively analysed into physico-chemical processes, or whether some explanatory concept irreducible to physics and chemistry must be invoked, is a debate that Kant did not settle but permanently shaped. It is worth noting that the imperative Kant made canonical — sapere aude (dare to know) — had earlier English expressions: Ambrose Philips’s Free-Thinker magazine adopted the Horatian phrase as its masthead in 1718, and the Earl of Shaftesbury had celebrated the spread of a “mighty Light” across England and Holland long before Kant formalized the Enlightenment’s self-understanding in 1784.(Porter, 2000)

Kant and Romantic Biology

Richards’s Romantic Conception of Life (2002) reconstructs Kant’s precise role in the founding of German Romantic biology. The principal figures of that tradition adopted a conception, given currency by Kant, Schelling, and Goethe, that regarded living nature as exhibiting fundamental organic types called archetypes — the four most basic animal structures usually discriminated were the radiata, articulata, mollusca, and vertebrata.(Richards, Robert J., 2002) Kant had maintained that the archetypal structure of organisms suggested they had been produced by the very ideal they embodied, an ideal that might reside only in an intellectus archetypus, a productive mind — the Divine mind.(Richards, Robert J., 2002)

Timothy Lenoir’s influential reading of Kant argued that the Romantic biologists (Reil, Kielmeyer, Blumenbach, von Baer) must be regarded as materialists and mechanists, with their construction of living organisms as teleological modeled only after Kant’s teleology als ob — a heuristic allowing good scientists to describe organisms as if they exhibited an intrinsically purposive structure, while mechanically reducing them in practice.(Richards, Robert J., 2002) Schelling and Goethe countered this reading: if archetypes proved a necessary methodological assumption for the biologist, then there was no reason, especially on Kantian grounds, to argue that nature was not intrinsically archetypal, essentially organic rather than mechanistic.(Richards, Robert J., 2002)

The Critique of Judgment provided the Romantic biologists with specific resources. Kant analyzed the logical similarity between teleological judgment and aesthetic judgment, and the Romantics took more to heart his finding that the two kinds of judgment were complementary approaches to nature, “approaches that penetrated to the same underlying object.” This meant that artistic experience and expression might operate in harmony with scientific experience and expression.(Richards, Robert J., 2002)

On the organism itself, Kant was explicit: “An organized being is thus not a mere machine: for the latter has only the power of motion, while the former has a formative power [bildende Kraft], of a kind that it imparts to materials not possessed of it (it organizes these materials). Hence such a propagative power of formation cannot be explained merely through the ability of motion that a machine has.”(Richards, Robert J., 2002) Yet Kant insisted this formative force and design in organisms was strictly regulative, not constitutive: a heuristic assumption allowing us to work out, if only partially, “the mechanical causes that we can suppose to be really operative in organic systems.”(Richards, Robert J., 2002)

Kant’s reading of Herder’s Ideen zur Philosophie der Geschichte der Menschheit drew out the monstrous implications of species transformation: with “a quaking irritation, he made these ideas explicit — ‘either one species would have arisen out of another and all out of one single original species or perhaps out of a single, productive mother-womb [i.e., the earth].’”(Richards, Robert J., 2002) Kant maintained that biology could not really be a science but at best only a loose system of uncertain empirical regularities, not a Naturwissenschaft but a Naturlehre.(Richards, Robert J., 2002) No mechanistic law, on the Kantian view, could strictly explain why or how the various media of the eye are so organized: “there could be no Newton of the grass blade.”(Richards, Robert J., 2002)

At the same time, Kant wrote to Blumenbach expressing genuine appreciation for his work on the Bildungstrieb: “In your new work, you unite two principles — the physical-mechanistic and the sheerly teleological mode of explanation of organized nature. These are modes which one would not have thought capable of being united. In this you have quite closely approached the idea with which I have been chiefly occupied.”(Richards, Robert J., 2002) Yet Kant drew a strict distinction the biologist himself did not make: the Bildungstrieb could at best function only as a regulative aid for the examination of mechanistic laws involved in organism formation; Blumenbach had “blissfully” used it as part of a constitutively causal account of organization.(Richards, Robert J., 2002) Kant himself entertained the possibility that “the maternal womb of the earth (like a large animal) might have given birth initially to creatures of a less purposeful form and these to others whose forms became better adapted to their place of origin” — a speculative passage that sits uneasily with his insistence that biology was not a true science.(Richards, Robert J., 2002)

See Also

• Tom Beauchamp and James Childress
• Hans Driesch
• Georges Canguilhem
• Henri Bergson
• Autonomy
• Categorical Imperative
• Teleology
• Vitalism
• Johann Friedrich Blumenbach
• Principlism

Sources

Richards, R.J. (2002). The Romantic Conception of Life: Science and Philosophy in the Age of Goethe. Chicago: University of Chicago Press. [Source ID: richards-romanticconception-2002]