1724-1804
Immanuel Kant was born in 1724 in Konigsberg, Prussia (now Kalingrad, Russia). He contributed to metaphysics, epistemology, ethics, and political philosophy. He lived most of his life in Konigsberg, where he died in 1804. He lived long enough to see the early stages of the French Revolution, which he initially welcomed because of its emphasis on both liberty and equality.
Kant’s philosophy emphasized the reconciliation of disparate themes and theories. In human nature he tried to reconcile the demands of heteronomy and autonomy. The latter has two distinct meanings: one ethical, the second metaphysical. In epistemology he tried to reconcile the competing claims of the rationalists—who emphasized a priori knowledge, primarily mathematics—with those of the empiricists, who claimed that all knowledge is based on experience. David Hume’s skeptical development of empiricist philosophy, Kant said, "interrupted my dogmatic slumber" (Kant [1783] 1953, p. 9). Humean skepticism threatened both traditional theism and the recently triumphant Newtonian science.
KANT’S COPERNICAN REVOLUTION
Kant wanted to defend religion from skeptical arguments and Newtonian science from a similar type of skepticism. He also defended a libertarian theory of human nature from the new determinism that many saw as implicit in Newtonian physics. This is the problem of heteronomy and autonomy. The former is the view that even human behavior is controlled by the same laws as the rest of the universe, implying that free will is an illusion. The latter is the view that not all human actions are dependent on (or deducible from) the laws of nature.
Kant’s theory of knowledge was based on a complex theory of categories of the mind that we have a priori (prior to, and independently of, experience) and that we apply to experience. Without it we could not have any coherent experience. It constitutes a third way of knowledge between a priori mathematical and logical concepts and those based on experience. It is synthetic a priori knowledge. Just as Copernicus reversed the roles of the sun and earth, so Kant reversed the role of thought and experience: We impose our mental categories on the world, not vice versa.
Kant argued that these concepts applied only to the world of experience and could not apply to metaphysical problems such as God, freedom, and immortality. He produced a complex critique of the three traditional theistic proofs (ontological, teleological, and cosmological) but also argued that reason could not disprove God’s existence, and then offered pragmatic proofs for such a belief. Kant’s Religion within the Limits of Reason Alone ([1787] 1960) was an attempt to replace religion based on revelation or fideism.
MORAL AND POLITICAL PHILOSOPHY
Kant’s moral philosophy was based on an ethical interpretation of autonomy culminating in his categorical imperative(s) and his proto-liberal political philosophy of freedom. The categorical imperative has two versions: "I ought never to act except in such a way that I can also will that my maxim should become a universal law" ([1797] 1964, p. 70) and the somewhat clearer, "act in such a way that you always treat … the person of any other, never simply as a means but always … as an end" ([1797] 1964, p. 96). The best interpretation of this is: "Don’t use people as if they were tools or machines; they are persons with independent wills and desires of their own." Because Kant assumed that people have conflicting wills and desires, he asserted that legislators must pass laws that protect everyone equally. Kantian equality is purely formal, meaning that laws must protect everyone equally, but he permitted massive material inequality, based on differences in everyone’s "talent, industry, and good fortune" ("Two Essays on Right" [1797] in Phelps 1973). Kant denied that there could be a principle of welfare or happiness, inferring from this that neither morality nor legislation could be based on experience Kant distinguished between perfect and imperfect duties. The former are based on the putative rights of others; the latter are not. Therefore, although animals do not have rights, we should not be cruel to them. Charity to the poor is another imperfect duty.
Despite the cosmopolitan character of his categorical imperative and political philosophy, Kant seemed to absorb from Hume an uncritical racism, especially concerning Africans. There are two ways in which one might defend either Kant or Hume. One would be the historicist argument, that we cannot judge people from different times and places by our contemporary standards. The other is to downplay the significance of these views in either philosopher in their overall philosophy. The latter is the more promising route because the eighteenth century was allegedly the age of Reason and Enlightenment. It also was the age in which slavery was first attacked on a widespread basis, leading to its eventual abolition in most of the world. Jeremy Bentham (1748-1832) argued for decent treatment for blacks, for animals, and (albeit secretly) for homosexuals, on the grounds that the key issue was not "Can they reason?" but "Can they suffer"? In addition, racism seems to conflict logically with Kant’s cosmopolitanism.
Kant’s greatest influence on the twentieth century may have involved his proposals for perpetual peace via a League of Nations. He also had great faith in republican governments to promote such peace better than monarchies would. In 1784 he wrote "What Is Enlightenment?" The basic idea was a willingness to dare to think for ourselves. His idea of autonomy, however, should not be confused with a "do your own thing" mentality: Instead, it meant that the laws we impose on ourselves are based on logically impeccable arguments.
