premise: A person of indeterminate sex wearing a dark hat, neutral pants, and a red shirt walking up a rocky slope at high altitude in the daytime. hypothesis: A person is getting ready to snowboard down a hill with one leg.
contradiction: One cannot go up a slope and down a hill at the same time.|contradiction: Walking is moving both legs and you snowboard by standing.|contradiction: A person can't walk up a hill and down it at the same time.