The present dissertation focuses on the examination of the methods of natural inquiry during the sixteenth-century. The historico-epistemological analysis of the different methodologies, which naturalists used to read the book of nature, shows that natural history, medicine, and alchemy were closely interconnected during the sixteenth-century. How did the naturalist thinkers justify and validate their knowledge? The present dissertation answers this question by means of two relevant historical examples of the pharmaceutical domain: Maranta’s theriac and Imperato’s philosophical medicine. They both show (...) the way in which experience and authority actually interacted within the naturalistic discourse of the sixteenth-century. In other words, the dissertation shows how experience aided naturalist philosophers to interpret correctly authorities and vice versa; more importantly, it shows under which circumstances experience could dethrone authority. In this manner, one can understand how the methods of natural inquiry justify and validate the pharmaceutical agenda of the sixteenth-century. (shrink)