  That Gassendi thinks there is a need for correctives on sensory information makes clear the depths of his rejection of epistemic foundationalism in Aristotelian or Cartesian thought: we cannot trust even information from the senses to give us a failsafe picture of the world. In this he embraces the Skeptical judgment that no source of belief can provide for certain knowledge. Yet he cannot accept their wholesale dismissal of sensory-derived evidence for belief. Knowledge from the senses is possible just in case we have warrant for judgments about appearances, though we may lack warrant for certainty about those judgments. To the limited extent that we have the second sort of warrant, he suggests, we find this in the reliability of our sensory apparatuses (as he describes in his Epicurean-inspired account of perception). We see here a ‘constructive skepticist’ response to the Skeptics who say no knowledge is possible and to those ancient and latter-day ‘dogmatic’ thinkers (including, in his view, the Aristotelians and Descartes) who say knowledge involves the attainment of certain belief—and is readily attainable. While it may not be possible to have certain beliefs, it is quite possible to have knowledge given that we construe it as justified but less-than-certain belief. (Naturally, it must have a veridical character as well, and Gassendi thinks it sufficient that such beliefs are at least truth-resembling.)