What’s the difference between science and philosophy? I don’t think there’s such a hard dividing line between the two, but there’s clearly some sort of difference.

We seem to be firmly in the area of empirical science when our basic observations can easily falsify hypotheses and scientific theoretical systems. Here’s a recent example of this. Out of CERN, researchers are saying that we may have discovered a new particle. What’s happened here, as with most contemporary scientific discoveries, is that there were accepted observations that could not be explained by our current theories and knowledge of the state of the world. Perhaps these unfitting observations were caused by a systemic database error. Perhaps our knowledge of how to observe electromagnetic waves is wrong. But with repeated tests and triple-checking, scientists decided that the best, most parsimonious explanation might be that what we once considered to be one type of particle is actually two different types.

Empirical science seems to have a relatively direct line to draw from ‘making observations’ to the ‘modification of concepts in our scientific theories’. That is, within science, the rigorous process for accumulating and updating scientific knowledge is rather well-defined. Particular scientific research appears rigorous if it meets the standards of this well-defined process. Particular concepts seem to be scientifically rigorous if they are well-defined enough to be studied through scientific research.

But not everything has a scientifically rigorous definition like the basic particles that are studied at the LHC. A chair doesn’t have a scientific definition, nor does art, nor consciousness, nor freedom. But we still use these concepts in everyday life because we find it useful to do so. Socially, we are capable of observing and effectively coordinating around concepts like chairs, art, consciousness, and freedom—nevertheless, the path from our basic empirical observations to updating our definitions of these everyday concepts is windy and ambiguous.

Philosophy exists in that windy and ambiguous conceptual space, where the link between empirical observations and useful concepts is not yet clear. It is the purpose of philosophy to clarify this windy and ambiguous road, so that we may discuss these useful concepts more rigorously. Philosophy sometimes clarifies concepts so rigorously that the subject matter can become a science. Physics, chemistry, biology—all used to be considered natural philosophy. But once enough work was done to explicate concepts—once it became easy to draw a line from our empirical observations to how we should update our theoretical systems—then it seemed to move into the realm of the sciences. Similarly too with the social sciences. While the concepts in social science are still much more vague than those of the ‘hard’ sciences, the concepts used by the social sciences seem to be rigorously-enough defined. The concepts can then be used to define relatively rigorous experiments which inform social scientific theories. People therefore consider these areas to be scientific (insofar as the research is rigorous).

Philosophy plays a role of conceptual clarification—the best philosophy focuses on conceptual clarifications which have practical benefit to us. Sometimes this practical benefit comes from explicating concepts so that science might study it rigorously. Here, we might think of how we went from descriptive taxonomies of animals to genetic taxonomies; or how Einstein clarified the notions of gravity and forces. Other times, we can find useful conceptual clarifications about moral and normative concepts, in the ways that they are linked to our observations and potential actions. This helps shape law and governing, and it helps clarify the motivations behind revolutions and other massive normative restructurings. Sometimes the clarification comes in how we carry out philosophy—here we might think of Aristotle and analytical philosophers’ work on logic, or philosophy of language folks figuring out limitations and preconditions of language use.

We should also note that what counts as rigor in science has evolved over time. What scientists used to think was a clear line from ‘observation’ to ‘how we ought to update our theories’ has changed, in part because philosophy helped clarify the concept of scientific rigor. Appeals to mystical beliefs, religious doctrine, and shot-in-the-dark theorizing shifted to naturalistic explanations of experimentally collected data with the Scientific Revolution. This further shifted to emphasize falsifications of null hypotheses with Popper in the 1950s. I think it is likely that we will continue to see advancements in things like our scientific norms, for example, the pre-scientific beliefs which inform us about which theories we find most plausible prima facie.

While I think I have added a bit of my own flair in the above paragraphs, it would be wrong to claim the main thrust of these ideas as my own. Wilfred Sellars described the concepts of a manifest image and a scientific image in ‘Philosophy and the Scientific Image of Man’ in 1963, and I first saw this described in Daniel Dennett’s Intuition Pumps and Other Tools for Thinking, pages 69-72. The manifest image is all of those concepts that we use in everyday life—color, people, tables and chairs, solidity, promises, free-will, etc. The scientific image is those rather extra-ordinary concepts that are created to understand (often unintuitive) experimental facts about the world—atoms, quarks, electromagnetic fields, molecules, and so on. Philosophy figures out how our concepts—manifest, scientific, whatever—“hang together” in some sense. Sometimes in this process of making sense of how our useful concepts are interrelated, we happen to explicate things from the manifest image into things that make sense to talk about in the scientific image. Such manifest-to-scientific translation tends to be pragmatically useful for reasons like added precision, reliability, and actionability.

Footnotes and Extra Bits

2021/07/11
— Added clarification about what I mean when I refer to ‘scientific rigor’: “That is, within science … to be studied through scientific research.”
— Added the caveat that not all people consider social science to be ‘science’, or consider it a lesser science: “(insofar as the research is rigorous)”