It’s a fine September day during freshman orientation week, and we’re a photo op: a circle of students on the grass outside a stately hall of higher education. Our leader asked us to tell each other what we hope to learn while we’re here. “I’m interested in metaphysics,” one girl says. I don’t know what that means, and being a clueless frosh, I don’t bother to find out until decades later. 
This is from Online Etymology:
“the science of the inward and essential nature of things,” 1560s, plural of Middle English metaphisik, methaphesik (late 14c.), “branch of speculation which deals with the first causes of things.” … See meta- + physics.
“The name was given c.70 B.C.E. … to the customary ordering of [Aristotle’s Physics], but it was misinterpreted by Latin writers as meaning “the science of what is beyond the physical.”
Metaphysics is what happens when scholars think about the big picture. René Descartes was doing metaphysics when he split reality into seen vs. unseen, knowable vs. mysterious: “He developed a metaphysical dualism that distinguishes radically between mind… and matter.” Encyclopaedia Britannica.
Metaphysics catches some grief about whether it’s a legitimate academic discipline, but counters that you can’t think about… well, anything… without first thinking about the bigger picture:
“Metaphysics, the philosophical study whose object is to determine the real nature of things—to determine the meaning, structure, and principles of whatever is insofar as it is. Although this study is popularly conceived as referring to anything excessively subtle and highly theoretical and although it has been subjected to many criticisms, it is presented by metaphysicians as the most fundamental and most comprehensive of inquiries, inasmuch as it is concerned with reality as a whole.”
Even science has to concede metaphysics’ primacy:
“It turns out to be impossible even to formulate a scientific theory without metaphysics, without first assuming some things we can’t actually prove, such as the existence of an objective reality and the invisible entities we believe to exist in it.
“This is a bit awkward because it’s difficult, if not impossible, to gather empirical facts without first having some theoretical understanding of what we think we’re doing.
“Choosing between competing theories that are equivalently accommodating of the facts can become a matter for personal judgment, or our choice of metaphysical preconceptions or prejudices.”
But Is It Science? Aeon Magazine, Oct. 7, 2019. (The remaining quotes are also from this source.)
Scientific inquiry begins subjectively — with beliefs and assumptions that can’t be scrutinized by scientific method — a detail which, if left unintended, puts scientific inquiry on a par with, let’s say, late night dorm conjecture about the meaning of life. Science tries to rise above by requiring that its theories be falsifiable: they have to be expressed in a way that lets you objectively prove them wrong.
“The philosopher Karl Popper argued that what distinguishes a scientific theory from pseudoscience and pure metaphysics is the possibility that it might be falsified on exposure to empirical data. In other words, a theory is scientific if it has the potential to be proved wrong.”
Falsifiability means you can’t appeal to metaphysics to avoid empirical scrutiny. Trouble is, our brains, once wired with our beliefs, make sure our experience conforms to them. But still…
“For me at least, there has to be a difference between science and pseudoscience; between science and pure metaphysics, or just plain ordinary bullshit.”
To be reliable, science has to make sure its metaphysics and physics line up in actual experience. For example, whatever your metaphysical theory of the grand cosmos, you still need physics to make your GPS work:
“When you use Google Maps on your smartphone, you draw on a network of satellites orbiting Earth at 20,000 kilometres, of which four are needed for the system to work, and between six and 10 are ‘visible’ from your location at any time. Each of these satellites carries a miniaturised atomic clock, and transmits precise timing and position data to your device that allow you to pinpoint your location and identify the fastest route to the pub. “But without corrections based on Albert Einstein’s special and general theories of relativity, the Global Positioning System would accumulate clock errors, leading to position errors of up to 11 kilometres per day. Without these rather abstract and esoteric – but nevertheless highly successful – theories of physics, after a couple of days you’d have a hard time working out where on Earth you are.
“In February 2019, the pioneers of GPS were awarded the Queen Elizabeth Prize for Engineering. The judges remarked that ‘the public may not know what [GPS] stands for, but they know what it is’. This suggests a rather handy metaphor for science. We might scratch our heads about how it works, but we know that, when it’s done properly, it does.”
More about falsifiability vs. faith, subjective vs. objective, real vs. fantasy, and other Cartesian dualisms next time.
 Now that I know what “metaphysics” means, I realize I was interested in it, too. In fact, metaphysics has been something of a defining pursuit of mine for most of my life, although less so lately. More on that another time.