That's not what you said "2 something, especially a clue, that is or intended to be misleading or distracting:"

Merriam Webster for fraud says:
b : an act of deceiving or misrepresenting : trick

Misleading, fraud, deceiving, misrepresenting are synonyms.

Or did you mean the nature of man is irreverent to a discussion of the nature of man?

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Greek philosophy regarding perfect beauty is irrelevant to medical prefrontal lesions.

Is that so? Check out this short piece on terminal lucidity in Psychology Today. Mental processes continue in spite of a physically incapable brain. How's that work?

The key elements in human thinking are not numbers but labels of fuzzy sets. -- L. Zadeh

Which explains a lot.