Roger Waters said he was inspired to write the classic Pink Floyd track Time (“Ticking away, the moments that make up a dull day . . . ”) when he realized that he was no longer preparing to do anything in life, but was simply in the middle of it. Many readers would agree with Waters’ sentiment, but it’s surprisingly hard to pin down exactly what he means. Is time a tangible substance with us in the middle? Does time have a direction? If so, where is it going, and when will it stop?
This line of questioning is more the purview of philosophy than rock music. In fact, as Adrian Bardon points out in this absorbing book, the problem of time—of what it is and how to think about it—has been one of philosophy’s central questions for almost three thousand years.
Bardon breaks down philosophical understandings of time into three main categories: idealism, which denies the objective reality of temporal change; realism, which sees time as a real underlying matrix for events; and relationism, a kind of middle path that sees time as an abstract tool we use to interpret change.
The Greek philosophers Zeno (who first posed the paradox of Achilles and the tortoise) and Parmenides introduce idealism, arguing that “time talk” is logically incoherent because to speak of the past and future is to speak of what is not. St. Augustine picks up on this line of thinking to address the theological problems that time presents for Christianity. Questions about what God may have been doing before creating the universe are null if time is a human invention.
Relationism is a product of Aristotle’s physics. Relationism differs from idealism in that it does not deny the reality of change, but still remains skeptical about any kind of objective temporality.
Isaac Newton changed everything. Newtonian physics suggest a realist, “absolute time,” an objective temporality that exists outside human perception. In the 20th century, Albert Einstein augmented Newton’s absolute time with the notion of “space-time”—the idea that the universe exists in all times and at all places in a sort of four-dimensional grid, an ether that encompasses all that has been, is, and will be.
This is where things get a bit tricky—for lay readers, at least. Buttressing his arguments with evidence from quantum physics and evolutionary psychology, Bardon, an associate professor of philosophy at Wake Forest University, argues that time is static. The sensation that time is flowing, he claims, is an evolutionary adaptation that allows us to make sense of the world, similar to our perception of color or texture.
The final third of the book explores the possibilities of time travel, how a static universe affects free will, and the temporal boundaries of the universe. Fascinating questions, worth spending many hours on—especially if you figure out how to get them back.