Introduction

In this chapter I discuss the epistemology of Immanuel Kant (1724–1804) and of a Kantian, Michael Friedman. Kant is a nativist. He holds that there are certain innate concepts, intuitions and beliefs that we use to organize our understanding of the world. According to Kant, these concepts, intuitions and beliefs are a priori in two senses. First, they are not learned. Second, the possibility of our having experience depends on our having these concepts, beliefs and intuitions. As we shall see, within Kant's system his innate beliefs are not empirically defeasible. Moreover, they provide many of our other beliefs with a priori justification.

Nativism, however, is only one of Kant's doctrines. As we shall see, some modern Kantians abandon nativism. For them, the important aspect of Kant's epistemology is the idea that we construct the world according to principles that we do not extract empirically from the world. They think that we impose these principles on the world. For Kantians, as for Kant, these principles are a priori.

In this chapter I discuss “theoretical philosophy” only in the Kantian sense of this term. Theoretical philosophy includes only metaphysics and epistemology. Kantian ethics, on the other hand, is what he calls “practical philosophy”. I examine Kantian ethics – or, rather, metaethics – in Chapter 9.

Kant on phenomena and noumena

Kant's theoretical philosophy has two central aims. First, he wants to defeat scepticism about the external world.