I am reading "On assertion and indicative conditionals" by Frank Jackson and have trouble with the following paragraph:
"The problem for the Equivalence thesis is to explain away the putative counter examples to 'P ⊢ (P → Q)' and 'Q ⊢ (P → Q), the only too familiar cases where despite the high probability of –P or of Q, and so of (P ⊃ Q), (P → Q) is not highly assertable."
I do not understand how 'P ⊢ (P → Q)' could be the case. As far as I know, this '–P ⊢ (P → Q)' is the paradox, with the negation of the antecedent, not without it as Frank states. How can you prove it?