The questions in this chapter are concerned with the doctrines of transcendental idealism as they relate to law. Transcendental idealism is a philosophy which is concerned with the attempt to view human ideas as possessing an autonomous existence. Human thought is perceived as ‘the exclusive support’ of the universe as known to man. In essence, Kant asked what can our understanding and reason know, apart from experience. His answer is: we do indeed possess a faculty of acquiring knowledge without appeals to our experience – namely, a priori knowledge. Two very important figures in the history of Western philosophy are considered in this chapter: Kant (1724-1804) and Hegel (1770-1831). Neither was a lawyer; each was a philosopher concerned with an examination of the essence of human thought. Neither had in mind the investigation of any existing legal system; each sought to derive principles of jurisprudential ideology from fundamental philosophic views. Both believed that man is a rational being capable of exercising free will, and stands separated from the rest of nature (and able to dominate it) because of that fact. Jurisprudential thought has been affected profoundly by Kant and Hegel, particularly in areas of scholarship concerning the essence of duty and responsibility, rights and duties, and the functions of the state.