你和我各有一个苹果，如果我们交换苹果的话，我们还是只有一个苹果。但当你和我各有一个想法，我们交换想法的话，我们就都有两个想法了。
If you have an apple and I have an apple, and we exchange apples, we both still only have one apple. But if you have an idea and I have an idea, and we exchange ideas, we each now have two ideas.
Science is not just a collection of facts; it is a way of thinking.
Tell the cook of this restaurant with my compliments that these are the very worst sandwiches in the whole world, and that when I ask for a watercress sandwich I do not mean a loaf with a field in the middle of it.