It is a damn poor mind indeed which can't think of at least two ways to spell any word.

Sometimes reported as having been a retort to statements of his political rival, John Quincy Adams, who had boycotted Harvard University's awarding of a Doctorate of Laws degree to Jackson in 1833, declaring "I would not be present to witness her [Harvard's] disgrace in conferring her highest literary honors on a barbarian who could not write a sentence of grammar and could hardly spell his own name." Quoted in News Reporting and Writing 4th edition (1987) by M. Mencher. / Unsourced variant: Never trust a man who has only one way to spell a word.

Likely misattributed