premise: Two young men are on a vast, level expanse of grass, and the man in the red shirt is catching the white Frisbee. hypothesis: The men are playing volleyball.
contradiction: They are playing different games as one is playing Frisbee and another is playing volleyball.|contradiction: Catching frisbees is a different game than playing volleyball, and are not done at the same time.|contradiction: Playing volleyball does not involve catching a frisbee.