Tractatus de Intellectus Emendatione

The Tractatus was first published in 1677, the year of Spinoza's death, by some of his closest friends, along with other works including the Ethica and the Tractatus Politicus. It is an attempt to formulate a philosophical method that would allow the mind to form clear and distinct ideas that are necessary for its perfection. It contains, in addition, reflection upon the various kinds of knowledge, an extended treatment of definition, and a lengthy analysis of the nature and causes of doubt. He discusses, among other topics, perception, experience, intelligence, memory, and forgetting.