4 ideas
| 17699 | Variables are auxiliary notions, and not part of the 'eternal' essence of logic [Schönfinkel] |
| Full Idea: A variable in a proposition of logic ....has the status of a mere auxiliary notion that is really inappropriate to the constant, 'eternal' essence of the propositions of logic. | |
| From: Moses Schönfinkel (Building Blocks of Mathematical Logic [1924], §1) | |
| A reaction: He presumably thinks that what the variables stand for (and he mentions 'argument places' and 'operators') will be included in the essence. My attention was caught by the thought that he takes logic to have an essence. |
| 17813 | Löwenheim-Skolem says any theory with a true interpretation has a model in the natural numbers [White,NP] |
| Full Idea: The Löwenheim-Skolem theorem tells us that any theory with a true interpretation has a model in the natural numbers. | |
| From: Nicholas P. White (What Numbers Are [1974], V) |
| 17812 | Finite cardinalities don't need numbers as objects; numerical quantifiers will do [White,NP] |
| Full Idea: Statements involving finite cardinalities can be made without treating numbers as objects at all, simply by using quantification and identity to define numerically definite quantifiers in the manner of Frege. | |
| From: Nicholas P. White (What Numbers Are [1974], IV) | |
| A reaction: [He adds Quine 1960:268 as a reference] |
| 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? |