Immanuel Kant (1724-1804) turned Hume’s Associationism on its head, saying already existing (i.e. “a priori”) concepts of “cause” enable us to have objective experiences. Kant also argued that innate reason alone cannot explain what does or doesn’t exist, which disagreed with Descartes’ Rationalism. Consequently, Kant’s Critique of Pure Reason (1781) presents the case for combining new experiences with existing ideas, i.e. “synthetic a priori propositions”.
