Translation of the initial chapters of Aristotle’s Prior Analytics into Portuguese and introduction, which addresses interpretative disagreements and translation choices.

I examine the difficulties involved in the Aristotelian proposal to identify the knowledge of “what it is” and “why it is”, in order to better understand the outlines that delimit it. I propose that the connections by which Aristotle links definition and explanation, and hence essence and cause, depend on the mutual convertibility between nominal expressions and predicative sentences.