2 ideas
15833 | Tell cleverness from answers, but wisdom from questions [Mahfouz] |
Full Idea: You can tell whether a man is clever by his answers. You can tell whether a man is wise by his questions. | |
From: Naguib Mahfouz (works [1998]) | |
A reaction: [Popped up on Twitter. I am adjusting to the 21st century] The observation is simplistic, of course, but very nice indeed. |
14238 | A class is an aggregate of objects; if you destroy them, you destroy the class; there is no empty class [Frege] |
Full Idea: A class consists of objects; it is an aggregate, a collective unity, of them; if so, it must vanish when these objects vanish. If we burn down all the trees of a wood, we thereby burn down the wood. Thus there can be no empty class. | |
From: Gottlob Frege (Elucidation of some points in E.Schröder [1895], p.212), quoted by Oliver,A/Smiley,T - What are Sets and What are they For? | |
A reaction: This rests on Cantor's view of a set as a collection, rather than on Dedekind, which allows null and singleton sets. |