In Allison Hills' paper "Moral Testimony" in Philosophy Compass, she refers to: i) p and ii) p'.
This is in the context of discussion one's ability to reason about p and q such that one can: "draw the conclusion that p'...from the information that q' (where p' and q' are similar but not identical to p and q)".
My question is, what logical effect does the apostrophe have when modifying p to p'?
Thank you for your help!