The Collaborative International Dictionary
Incogitance
Incogitance \In*cog"i*tance\, Incogitancy \In*cog"i*tan*cy\, n. Lack 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.
Wiktionary
incogitance
n. incogitancy