“The example of the jet engine can help us to clear up another confusion. Science, according to many scientists, concentrates essentially on material causation. It asks the “how” questions: how does the jet engine work? It also asks the “why” question regarding function: why is this pipe here? But it does not ask the “why” question of purpose: why was the jet engine built? What is important here is that Sir Frank Whittle does not appear in the scientific account. To quote Laplace, the scientific account has “no need of that hypothesis”.29 Clearly, however, it would be ridiculous to deduce from this that Whittle did not exist. He is the answer to the question: why does the jet engine exist in the first place?”