Hi Paul, what you are remembering is a paraphrase of something Bergson said in his book Creative Evolution. He was using analogies to explain the difference between deductive reasoning (science) and intuition. He says that from our knowledge of walking, we can never deduce that swimming is possible. Only by entering the water can we come to learn that swimming is possible and how to do it. We learn through experience. not thinking. It is an argument similar to David Hume's, who said that we could never learn that we would drown in water by simply looking at water and thinking about it. That connects with one of my favorite ideas in philosophy, William of Ockham's declaration that logic tells us nothing about the world. We must experience the world to learn about it.