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Single Idea 16687

[filed under theme 26. Natural Theory / A. Speculations on Nature / 7. Later Matter Theories / c. Matter as extension ]

Full Idea

Bodies are those substances in which one finds three dimensions.

Gist of Idea

Bodies are three-dimensional substances

Source

Thomas Aquinas (Summa Theologicae [1265], Ia Q18.2c), quoted by Robert Pasnau - Metaphysical Themes 1274-1671 16.2

Book Ref

Pasnau,Robert: 'Metaphysical Themes 1274-1671' [OUP 2011], p.324

A Reaction

Pasnau points out that this extensional view of physical bodies was a commonplace long before Descartes. Presumably there are also non-dimensional substances (such as angels?).

The 8 ideas with the same theme [matter is just whatever occupies a space]:

16687 Bodies are three-dimensional substances [Aquinas]
16684 Impenetrability only belongs to the essence of extension [Descartes]
16601 Matter is not hard, heavy or coloured, but merely extended in space [Descartes]
6518 Matter can't just be Descartes's geometry, because a filler of the spaces is needed [Robinson,H on Descartes]
13185 Even if extension is impenetrable, this still offers no explanation for motion and its laws [Leibniz]
16683 Leibniz eventually said resistance, rather than extension, was the essence of body [Leibniz, by Pasnau]
5615 Extension and impenetrability together make the concept of matter [Kant]
6519 Locke's solidity is not matter, because that is impenetrability and hardness combined [Robinson,H]