Alternatively: One case refers to hefker declared in the presence of two; the other, if declared before three. For R. Johanan said in the name of R. Simeon b. Jehozadak: Hefker declared in the presence of three is valid, but not in the presence of two. R. Joshua b. Levi said: By the Torah, it is hefker even if declared in the presence of one: why then are three required? So that one can take possession, and the other two attest it. To Part b