Conversation so far:
what was the revival of casuistry?
By reviving casuistry (also known as case ethics), Toulmin sought to find the middle ground between the extremes of absolutism and relativism.
what were some of his beliefs about this?
Casuistry employs absolutist principles, called "type cases" or "paradigm cases," without resorting to absolutism.

Question: can you tell me more about these "cases"?
Self-contained rewrite: Can you tell me more about "type cases"?