"On the Improvement of Ethical Intellect" is Spinoza's work on methodology and epistemology. This book was probably written by him from the winter of 1661 to the spring of 1662. Because he mentioned the manuscript of this article in a letter to Oldenburg around April 1662. This is an unfinished work. Although unfinished, it is still an independent treatise that can be concluded and rich in content, and can be read as an introduction to his central work "Ethics". In the small notes he added to this article, there are several places where he often mentions "I will explain it in my philosophy."
