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Infinity

Key terms
The word
In number and magnitude
In thought
God and man

Limit and the limitless

What does it mean for something to have no end? A limit is what makes a thing definite, and the infinite is what lacks one. These readings ask how the limitless can be understood and what it means to call something endless.

3 readings

In the Philebus, Plato has Socrates and Protarchus sort the things in the world into classes, and here Socrates refers to what admits of “more or less” as belonging to “the class of the infinite”, set against “the mark or seal” of limit. The dialogue concerns the good life, and this classification is its metaphysical ground. The passage stands under this term as the ancient pairing of the infinite with the finite.

Book III of Aristotle’s Physics treats the infinite, and in chapter 6 he says that it “turns out to be the contrary of what it is said to be”, since it is not what has nothing outside but what “always has something outside it”. He uses the ring without a bezel as his illustration. Book III is the standard ancient discussion. The passage stands under this term as his correction of the common account.

Section 22 of Hegel’s Philosophy of Right (1821), in the Introduction on the will, distinguishes the true infinite from the “bad infinite”. The Addition, taken from his lectures, says that the infinite is rightly represented as a circle and that the “free will is truly infinite”. It stands under this term as the contrast of a line that does not return and a circle that does.