4 ideas
8970 | Our notion of identical sets involves identical members, which needs absolute identity [Hawthorne] |
Full Idea: Our conceptual grip on the notion of a set is founded on the axiom of extensionality: a set x is the same as a set y iff x and y have the same members. But this axiom deploys the notion of absolute identity ('same members'). | |
From: John Hawthorne (Identity [2003], 3.1) | |
A reaction: Identity seems to be a primitive, useful and crucial concept, so don't ask what it is. I suspect that numbers can't get off the ground without it (especially, in view of the above, if you define numbers in terms of sets). |
21432 | Culture is the struggle to agree what is normal [Gibson,A] |
Full Idea: Culture is the struggle to agree what is normal. | |
From: Andrew Gibson (talk [2018]) | |
A reaction: A nice aphorism. Typically the struggle took place in villages, but has now gone global. The normalities of other cultures are beamed into a remote society, and are frequently unwelcome. |
1748 | Archelaus was the first person to say that the universe is boundless [Archelaus, by Diog. Laertius] |
Full Idea: Archelaus was the first person to say that the universe is boundless. | |
From: report of Archelaus (fragments/reports [c.450 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 02.Ar.3 |
5989 | Archelaus said life began in a primeval slime [Archelaus, by Schofield] |
Full Idea: Archelaus wrote that life on Earth began in a primeval slime. | |
From: report of Archelaus (fragments/reports [c.450 BCE]) by Malcolm Schofield - Archelaus | |
A reaction: This sounds like a fairly clearcut assertion of the production of life by evolution. Darwin's contribution was to propose the mechanism for achieving it. We should honour the name of Archelaus for this idea. |