"Everything in moderation" is a common view. But then moderation should be in moderation. If so, isn't moderation not fully moderate, and thus is partly immoderate?

Wonderful question. In Ancient Greco-Roman philosophy there was debate and disagreement about such a matter: some philosophers thought moderation in terms of appetites should be strict and without exception, whereas others thought the occasional immoderate indulgence was reasonable (for some, a person might on occasion over consume wine while still having living a life dedicated to the love of wisdom).

One way to address the paradox you raise is to distinguish levels of moderation, thus restricting the "everything" in the injunction "Everything in moderation." So, if one alters the original claim to (for example) 'a person who loves wisdom should exercise moderation in satisfying their appetites and first-order desires (e.g. avoiding gluttony),' one avoids the idea that one should only be moderate in following this dictum.

The kind of paradox you raise comes up in other areas. For example, if we consider a dictum that 'persons should be tolerant,' does this dictum require persons to be tolerant of intolerance? As in the case of moderation, I think that one avoids (or lessens?) the paradox once 'toleration' is spelled out such that we come to appreciate that toleration is not something we see as virtuous (or sensible) if it is completely unrestricted. The same point might be made in a fuller unpacking of advancing moderation as a virtue. Presumably, none of us thinks that cruelty, injustice, murder, rape.... are acceptable if they are done in "moderation."

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