Proto-objects, I claim, are the necessary conceptual building blocks for an idea of an object that admits of perfect identity. Also, ideas of objects that admit of perfect identity, must, according to Hume, be imagined. In this chapter, we examine Hume's somewhat implicit first account of perfect identity, given in 1.3.2. In the course of doing so, we begin to see how and why proto-objects enable us to imagine objects that admit of a perfect identity. However, the reader should note that this chapter merely serves as an introduction to Hume's theory of imagined causes and perfect identity, while Chaps. 6, 7, and 8 provide us with a more fully-developed version.