Today we begin our discussion of Plato’s Theaetetus. We start by considering how some of our friends answered the question: What is knowledge? Then, we discuss the difference between knowledge and the kinds of knowledge and we briefly go over Socrates’ famous midwife passage. We end by inquiring in a preliminary way into the relationship between Theaetetus’s claim that knowledge is perception and Protagoras’s that man is the measure of all things.