A proposition is equivalent to it being implied by \( \top \). Closed form of mptru. Dual of dfnot. It is to tbtru what a1bi is to tbt. (Contributed by BJ, 26-Oct-2019.)
A proposition is equivalent to it being implied by \( \top \). Closed form of mptru. Dual of dfnot. It is to tbtru what a1bi is to tbt. (Contributed by BJ, 26-Oct-2019.)