In this lecture Dallas set out to outline Aristotle’s Metaphysics, highlighting parts which few do and drawing attention to the theme of the unity which is in a thing, namely Aristotle’s concept of secondary substance. He begins with Book 1, recommends that one work through Book 3, and then turns to book 4 (14:30). Book 4 deals with the first aporia “whether the investigation of the causes belongs to one or more sciences.”
Around 20:00 he starts to discuss Book 5 in which Aristotle defines terms, including “cause” and “substance.” Note the second type of substance “that which being present in such things . . . is the cause of their being.” And the fourth type of substance. Dallas then (28:00) tries to make sense of a very difficult passage of Aristotle in which he gives two senses of substance (primary and secondary). Regarding the second, Dallas reminds students of other passages in Aristotle where he says that a thing is identical with its essence. He says for Aristotle the fundamental conception of being in Aristotle is independence. Being, for Aristotle, is that in a thing upon which everything else about it depends.
Around 40:30 he turns to Book 6 and the primacy and nature of substance. For the next four books Aristotle, says Willard, will only discuss one category of substance (though he has others). Willard notes that Aristotle will speak of things which have movement in themselves but he means change (there are six kinds) and not just locomotion.
Around 48:30 he turns to Book 7 in which he starts to emphasize that for Aristotle the substance is the essence or the form. This is also for Aristotle the primary cause in a thing (not the efficient or final cause). What makes a thing what it is (its principle or cause), Willard says, is the unity of form and matter. Dallas asks, what is it that makes this wood (the matter) a table? It is the essence (the form) which is a power which organizes things, giving it a unity. Interestingly, for Aristotle, the particular matter does not matter and can be substitute for another. What cannot be replaced and still be the same thing is the form or essence.