presupposition

…is equivalent to forming the presupposition of the question. For example, suppose that this is done in the desideratum of the question “Who murdered Dick?”—viz., in “I know who murdered Dick,” or symbolically K_I(∃x/K_I) M(x,d). Then the result is K_I(∃x) M(x,d), which says, “I know that someone murdered Dick,” which…