Combining Texts

All the ideas for 'fragments/reports', 'Letters to Thomasius' and 'Knowing One's Own Mind'

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4 ideas

9. Objects / D. Essence of Objects / 1. Essences of Objects
The essence of a circle is the equality of its radii [Leibniz]
     Full Idea: The essence of a circle consists in the equality of all lines drawn from its centre to its circumference.
     From: Gottfried Leibniz (Letters to Thomasius [1669], 1669)
     A reaction: Compare Locke in Idea 13431 and Spinoza in Idea 13073 on the essence of geometrical figures. A key question is whether the essence is in the simplest definition, or in a complex and wide-ranging account, e.g. including conic sections for circles.
13. Knowledge Criteria / E. Relativism / 2. Knowledge as Convention
By nature people are close to one another, but culture drives them apart [Hippias]
     Full Idea: I regard you all as relatives - by nature, not by convention. By nature like is akin to like, but convention is a tyrant over humankind and often constrains people to act contrary to nature.
     From: Hippias (fragments/reports [c.430 BCE]), quoted by Plato - Protagoras 337c8
18. Thought / C. Content / 6. Broad Content
External identification doesn't mean external location, as with sunburn [Davidson, by Rowlands]
     Full Idea: Davidson observes that the inference from a thought being identified by a relation to something outside the head does not entail that the thought is not wholly in the head, just as sunburn is identified by external factors, but is still in the skin.
     From: report of Donald Davidson (Knowing One's Own Mind [1987]) by Mark Rowlands - Externalism Ch.8
     A reaction: Rowlands (an externalist) agrees, and this strikes me as correct, and it needs to be one of the fixed points in any assessment of externalism.
27. Natural Reality / A. Classical Physics / 1. Mechanics / a. Explaining movement
Bodies are recreated in motion, and don't exist in intervening instants [Leibniz]
     Full Idea: I have demonstrated that whatever moves is continuously created and that bodies are nothing at any time between the instants in motion.
     From: Gottfried Leibniz (Letters to Thomasius [1669], 1669.04), quoted by Daniel Garber - Leibniz:Body,Substance,Monad 1
     A reaction: Leibniz is a little over-confident about what he has 'demonstrated', but I think (from this remark) that he would not have been displeased with quantum theory, and the notion of a 'quantum leap' and a 'Planck time'. A 'conatus' is a 'smallest motion'.