Drat: a ‘small’ mistake in Category Theory I

Just spotted an elementary thinko in Category Theory I.

I carelessly define a finite limit as a limit over a diagram with a finite number of objects. But standardly, it should of course be “with a finite number of objects and finite number of arrows”. And I define a small limit as a limit over a diagram with no more than set-many objects: it should of course be “with no more than set-many objects and set-many arrows”.

No great harm done as the definitions do little work in Category Theory I but were really for future use in Part II. Very annoying all the same. And the twin mistakes have been there in however many earlier iterations, and no-one has pointed them out.

I’ll have to start a corrections page …

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