A writer needs three things, experience, observation, and imagination, any two of which, at times any one of which, can supply the lack of the others.

Faulkner’s remark frames literary creation as a balance of three faculties: lived experience (what one has endured), observation (what one notices in others and the world), and imagination (the power to transform and invent). The second clause—“any two…at times any one”—argues against a single prerequisite for art: a writer short on worldly experience can compensate through acute attention and inventive empathy; a writer with limited imagination may still produce truth through careful witnessing and honest recollection. The statement also implies that these elements are not additive but substitutive in practice, and that strong writing often arises from an intense development of one capacity that can stand in for the others.