I think that last point (Hoffmann post) is right too. So I'd be committed to: basic-ness has the force of primitive-ness; if not not. Jackson, by the way, a little like a number of other people, reduces the significance of some related intuitive dependencies, and then explicates, as he would say 'meaning relations' in terms of possibilities. He then has dividers among those possibilities, allowing for metaphysical and conceptual truths (roughly). However, the philosopher (very roughly) gets to push some buttons marked A or C intension in order to have some of these possibilities later collide -- that is, according to suitably informed reports. One can take the thesis as remarking inevitability (if not quite infallibility) of the colliding procedure, according to reports. So it's a kind of mean spirited Quinean take on infallibility and justification by way of involved essentialism that actually makes room for the infallibly justified (in that mean sense which may not interest you).