Figuring out the meaning and syntax of the English translation of Charmides

Solution 1:

There's an extraposition in there.

A more normal order would be

Can that which does not make men good be good?

but (especially in writing) this is less comprehensible, because of the difficulty of finding the end of the relative clause which does not make men good.

Also that which ... is somewhat literary: a more ordinary form would be something which.

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