John Cook Wilson -- on taking for granted, not knowing -- Grice's sharp criticism

From M. Marion's entry on J. C. Wilson in the Stanford Encyclopaedia:

"H. P. Grice put forth a common objection

when he argued that Cook Wilson's position

leaves

----- “no room for the
----- possibility of thinking
----- that we know p when
----- in fact it is not the case that p”,

while the introduction of the state of ‘being under the impression that’ does not solve the problem:

----“for what enables us to deny that
---- all of our so-called knowledge
----is really only ‘taking for granted’?” (Grice 1989, 383–384).