Week 4: The Watch and the Watchmaker, William Paley
After the arguments given by Aquinas and other medieval philosophers, this argument by William Paley is one of the most famous and influential arguments for the existence of God. Paley’s argument takes the form of an argument from analogy. An argument from analogy starts from the premise that two things or groups of things are similar; it is then added that since one of the things or groups has some attribute or property, the other should have that property as well. For instance, you might reason that since your older child liked rubber duck bath toys as an infant, and since your younger child is now an infant, your younger child will like rubber duck bath toys as well. The idea is that since the children are similar, what was true of one is true of the other.
Paley argues that the natural world around us (and including us) and a watch are similar in their complexity. This is the premise that establishes the similarity between the two things—here, a watch and nature. The second premise then says that what is true of one should be true of the other. What’s true of one, according to Paley, is that if you found a watch “in crossing a heath”, you would suppose that someone had designed it—that is, you would explain the existence of the watch by claiming that there had been some intelligent being who had designed and fashioned it. Thus, adds Paley, you should make the same supposition about nature. In experiencing its complexity, you should—as you did with the watch—come to believe that some intelligent being had designed nature and brought it into existence. This being, of course, would be God. Thus, Paley thinks he has established that it is rational to believe that there is an intelligent God who designed and created the world as we find it.
Arguments from analogy have four parts that it’s helpful to know if you’re going to evaluate one.
1. The data object or group—the thing you already know something about. In Paley’s argument the watch is the data object.
2. The inference object or group—the thing that the conclusion is about. In Paley’s argument, it’s nature.
3. The given attribute—this is the feature or property observed of or known to obtain in the data object or group. This, of course, is the watch’s attribute of having been fashioned by an intelligent being.
4. The projected attribute—this is the feature or property claimed to belong to the inference object or group. Here, the projected attribute is the same as the given attribute: having been fashioned by an intelligent being.
An argument from analogy uses the similarities between the data object and the inference object and the fact that the data object has the given attribute to justify the claim that the inference object has the projected attribute. Thus, these arguments are generally stronger when the data object and the inference object are similar in ways that are relevant to the given and projected attributes. Remember the reasoning about infants and duck toys? It was reasonable because the kids are similar in ways that are relevant to which sorts of toys they’ll like—infants tend to like pretty much the same things. But compare that reasoning to the following: dogs and cats are similar; dogs bark, so cats do too. This argument from analogy is poor because the similarities between dogs and cats (e.g. relative size, being domesticated, etc.) aren’t relevant to the sounds they make.
I say all this, of course, to encourage you to evaluate Paley’s argument from analogy. Is a watch similar to the universe in ways that are relevant to Paley’s conclusion?