Full Idea
I say Mary knows an old fact in a new way, but I do not find a new bit of knowledge and a new fact.
Gist of Idea
I say Mary does not have new knowledge, but knows an old fact in a new way
Source
comment on Frank Jackson (What Mary Didn't Know [1986]) by John Perry - Knowledge, Possibility and Consciousness §7.3
Book Reference
Perry,John: 'Knowledge, Possibility and Consciousness' [MIT 2001], p.159
A Reaction
This seems roughly the right way to attack Jackson's 'knowledge argument', by asking exactly what he means by 'knowledge'. It is hard to see how 'qualia' can be both the means of acquiring knowledge, and the thing itself.