incogitancy

In*cog"i*tance, In*cog"i*tan*cy, n. Etym: [L. incogitantia.] Defn: Want of thought, or of the power of thinking; thoughtlessness; unreasonableness. 'T is folly and incogitancy to argue anything, one way or the other, from the designs of a sort of beings with whom we so little communicate. Glanvill.

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