Dallas, in this lecture, picks up again the theory of distinctions put forward by Suarez and also Descartes. Be sure to catch the idea that not everything that can be distinguished can be separated. Next Dallas takes students through a handout with a list of concepts. The substance of that handout is in the transcript section below. Though this may seem unnecessary, often arguments will trade on treating things as identical when they are merely similar, indistinguishable, inseparable, dependent, united, related, equal or equivalent. Then at the end of the lecture Dallas will sum up philosophy into four main problems.
A list of Concepts related to and often confused with or mistakenly related to identity and difference:
1. Similarity — Dissimilarity
2. Indistinguishability — Distinguishability
3. Inseparability — Separability
4. Dependence — Independence
5. Unity — Disjunction
6. Relation — Non-relation (Unrelatedness)
7. Equality — Inequality
8. Equivalence — Inequivalence