structure for 'Thought'    |     alphabetical list of themes    |     expand these ideas

18. Thought / D. Concepts / 6. Abstract Concepts / d. Abstracta by example

[defining abstract entities by offering examples]

2 ideas
The Way of Example compares donkeys and numbers, but what is the difference, and what are numbers? [Lewis]
'Abstract' is unclear, but numbers, functions and sets are clearly abstract [Field,H]