Intelligence Gained On Earth is Permanent — William Clayton (April 2, 1843)
Whatever principal of intelligence we obtain in this life will rise with us in the resurrection: and if a person gains more knowledge in this life through his diligence & obedience than another, he will have so much the advantage in the world to come.
Instruction, 2 April 1843, as Reported by William Clayton, p. 70, The Joseph Smith Papers.
God Cannot Create Intelligence — Wilford Woodruff (April 7, 1844)
. . . if I am right I might say God never had power to create the spirit of man, God himself could not create himself. Intelligence is Eternal & it is self exhisting
Discourse, 7 April 1844, as Reported by Wilford Woodruff, p. 137, The Joseph Smith Papers.