There are three technologies a modern AI-aware software engineer needs to know: data mining, theorem proving, and nonlinear optimization (also called search-based SE). While much of the current industrial AI activity is focused on data mining, these other technologies are starting to achieve prominence. Optimization technology is discussed in the editorial “A Watershed Moment for Search-Based Software Engineering” (see IEEE Software, July-August 2021). Here, we offer a tutorial on theorem proving (what it is, how to use it, how it can sometimes go wrong, and how to fix that).