Unlaws: the missing “dark matter” in the philosophy of science?

Science is sometimes defined as the systematic study of the physical world with the aim of discovering laws of nature. Laws embody generalizations connecting different phenomena, often involving a causal link between one concept and another. I suggest that much of science in fact depends on the opposite idea: the “unlaw”, defined as the proposition that two variables have no causal or mathematical link with one another. This idea unifies such apparently distinct notions as thought experiments, conservation principles in physics and experimental design paradigms in the life sciences, as well as highlighting the importance of diversity in the human condition. I propose that the importance of unlaws be acknowledged, and that this category be given due consideration in the philosophy of science, where it may help to resolve some persistent misunderstandings.