3 ideas
13166 | Essences are no use in mathematics, if all mathematical truths are necessary [Mancosu] |
Full Idea: Essences and essential properties do not seem to be useful in mathematical contexts, since all mathematical truths are regarded as necessary (though Kit Fine distinguishes between essential and necessary properties). | |
From: Paolo Mancosu (Explanation in Mathematics [2008], §6.1) | |
A reaction: I take the proviso in brackets to be crucial. This represents a distortion of notion of an essence. There is a world of difference between the central facts about the nature of a square and the peripheral inferences derivable from it. |
74 | Even God could not undo what has been done [Agathon] |
Full Idea: One thing is denied even to God: to make what has been done undone again. | |
From: Agathon (plays (frags) [c.410 BCE]), quoted by Aristotle - Nicomachean Ethics 1139b09 | |
A reaction: a quotation - cf the Euthyphro Question |
6005 | Animals are dangerous and nourishing, and can't form contracts of justice [Hermarchus, by Sedley] |
Full Idea: Hermarchus said that animal killing is justified by considerations of human safety and nourishment and by animals' inability to form contractual relations of justice with us. | |
From: report of Hermarchus (fragments/reports [c.270 BCE]) by David A. Sedley - Hermarchus | |
A reaction: Could the last argument be used to justify torturing animals? Or could we eat a human who was too brain-damaged to form contracts? |