The theory doesn’t explain anything other than the phenomenon it explains.
- My cat likes tuna because she’s a cat. (This theory asserts only that cats like tuna, without explaining why cats like tuna. It thus does not explain why my cat likes tuna.)
- Ronald Reagan was militaristic because he was American. (True, he was American, but what was it about being American that made him militaristic? What caused him to act in this way? The theory does not tell us, and hence, does not offer a good explanation.
- You’re just saying that because you belong to the union. (This attempt at dismissal tries to explain your behaviour as frivolous. However, it fails because it is not an explanation at all. Suppose everyone in the union were to say that. Then what? We have to get deeper – we have to ask why they would say that – before we can decide that what they are saying is frivolous.)
Identify the theory and the phenomenon it explains. Show that the theory does not explain anything else. Argue that theories which explain only one phenomenon are likely to be incomplete, at best.