The talk was in a training symposium for people starting out in academic psychology. People at various stages of their careers were invited to talk about how we approach research. I titled my talk “Making Progress in the Hardest Science,” and the first third of the talk was a half-serious, half joking explanation of the title.
The idea is that you often hear people arrange the sciences on a continuum from “hard” to “soft,” with physics at the hard end and psychology at the soft end. The implicit message is that the “hard” sciences are more scientific. But that’s not based on anything fundamental or substantive. As best as I can tell, it’s about scienciness. We have these preconceptions and stereotypes about what science is supposed to be about — big fancy equipment, lab coats, etc. But that’s not science. That’s the superficial sheen of scienciness.
What science is is a method of inquiry. In a nutshell, it’s the application of logic to empirical evidence. And by that measure, physics and biology and psychology are equally and fully scientific, because we’re all trying to figure stuff out by systematically gathering evidence and applying logic to it. (Or at least our respective academic versions are. I offer no defense of the Doctor Firstnames in your local bookstore.)
So it doesn’t make sense to try to determine who is more scientific. Instead, what differs is what we are trying to figure out — the phenomena we strive to understand. And here I think the other meaning of “hard” is useful.
What are the “hard” — as in difficult — problems in science? Hard problems in science are those that are embedded in complex systems; they are hard because to study something well you often need to isolate it from outside influences. Hard problems are those that vary by local conditions — science seeks to identify general laws, and when something is locally dependent, you need to sniff out the complex interactions that make it so. And hard problems are those that are difficult to quantify — science rests upon formalization and quantification, and you need to get traction at that initial step of quantification (i.e., measurement) before you can test theories. So… by these measures, if we are going to differentiate areas of science, the continuum of scientific problems should go from “hard” to “easy,” and psychology is clearly a science that deals with hard problems. Perhaps the hardest.
This was mostly intended as cheerleading to an audience of budding academic psychologists, revolving around a debatably clever pun. (I don’t really mean to suggest that physicists and chemists are picking the low-hanging fruit of the scientific disciplines. The low branches were picked clean centuries ago.) But the human mind is an amazingly complicated thing to study, which is what makes psychology so much fun.