In other works, Lackey argues that reasonableness, rather than knowledge, is the norm of assertion,[18] that memory is a generative epistemic source,[19][20] and that lying requires deception.

[21] Lackey is also known for arguing against the claim central to virtue epistemology that knowledge should be understood in terms of the knower's deserving credit for the truth of her belief.

[22] Lackey argues that the virtue epistemologist faces a dilemma: either the standards for deserving credit for a true belief are relatively high, or they are relatively low.

If they are relatively high, then the virtue epistemologist cannot account for instances of knowledge from testimony, where the credit for the hearer's true belief goes to the speaker.

[28] Lackey was elected an at-large member of the board of officers for the American Philosophical Association in the first-ever association-wide vote for this position.