Leibniz: Why Did We Stop Asking Why?

The Greek philosopher Aristotle (384 – 322 BC) believed that there were four kinds of causes:

1. A material cause (the laptop on which I’m writing consists of certain matter, and in that sense the matter is the cause of my computer’s existence)
2. A formal cause (my laptop has a certain shape and form)
3. An efficient cause (a certain company has made my computer, using various technologies to do so, and this “art of computer-making” is the efficient cause; the “how”)
4. A final cause (that for which the computer was intended by the company, namely for me to sit here and write this post; the “why”)

Now I recently read the Discourse on Metaphysics by Gottfried Leibniz (1646 – 1716). In it, he laments the fact that Newton and his followers (“our new philosophers”) decided to banish all discussions of final causes from “Physics” (more or less equivalent with what we now call “science”). Newton famously said, “I will not feign a hypothesis,” by which he meant mostly that he would not try to explain why gravity exists, but only concern himself with how it worked.

This decision to limit science to the question of how and excluding the question of why is still with us today—quite to the dismay of Leibniz, I think, if he were alive. He would ask: “Why do we stick with this decision to banish final causes from scientific discussions? Let’s bring them back in. Explaining efficient causes is good. Let’s retain that. But explaining final causes is also good. Why did we throw them out? The best plan would be to join the two ways of thinking.”

What do you think? Was Newton right to banish final causes from science, or should we attempt to bring efficient causes and final causes together, not just in religious and philosophical discourse, but actually in science? I am inclined to think that science should confine itself to the “how” questions, but it’s not a conclusion one should reach lightly.