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Ladder

Homotopy — the ladder

One essay so far against this idea. A ladder is the distinct arguments that stand against one idea, and this one has room to grow.
  1. 0 times round1 time round2 times roundthe number under each loop is counted by walking it and adding the angle turned through, as seen from the holea loop can be slid and stretched at will inside the ring without changing that number, and there is no way tochange it without leaving the ring

    A loop that cannot be pulled tight

    A hole is a strange thing to point at, because it is precisely where the surface is not. What can be pointed at is a loop of string lying on the surface — and the hole announces itself by refusing to let that loop be pulled in to a point.

    rung 1 · topology

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