Forethought

I don't think Tom did that with any forethought.

Tom usually acts without forethought.

Tom says whatever comes into his head without forethought.

Near-synonym: foresight

With a little forethought we'd have planned for this contingency and not been stuck here now.

c. 1613–1621, Francis Bacon, The judicial charge upon the commission of Oyer and Terminer held for the verge of the Court Forethought malice.