This book was recommended in a writer's group I was in. There's two basic parts. Examples of character traits in scenic action and explanations of the traits.
About 50 traits, which is a nice breakdown that could take one-dimensional chars to two-dimensions. Good substance for secondary characters.
The psychological explanation didn't convince me, but my time was well-spent with the trait list.
This was an archaic investigation of human nature fueled largely by gross stereotypes. Not without value but adding little to a real understanding of others.