from St. John's College in Annapolis, Maryland in 1990 and went on to graduate school at Penn State University to earn a master's degree, studying under philosopher Alphonso Lingis, in 1991.

While pursuing a Ph.D. at DePaul University, Harman worked as an online sports reporter, an experience which he credits for developing his writing style and productivity.

Harman is considered part of the speculative realism trend, a nebulous grouping of philosophers united by two perspectives: a rejection of anthropocentric "philosophies of access" which privilege the perspective of humans in relation to objects, and a support of metaphysical realism via rejection of "correlationism", an assumption in Post-Kantian philosophy that fellow speculative realist Quentin Meillassoux defines as "the idea according to which we only ever have access to the correlation between thinking and being, and never to either term considered apart from the other.

[14] Cutting across the phenomenological tradition, and especially its linguistic turn, Harman deploys a brand of metaphysical realism that attempts to extricate objects from their human captivity and metaphorically allude to a strange subterranean world of "vacuum-sealed" objects-in-themselves: "The comet itself, the monkey itself, Coca-Cola itself, resonate in cellars of being where no relation reaches.

"[15] Strongly sympathetic to panpsychism, Harman proposes a new philosophical discipline called "speculative psychology" dedicated to investigating the "cosmic layers of psyche" and "ferreting out the specific psychic reality of earthworms, dust, armies, chalk, and stone.

"[16] Harman does not, however, unreservedly endorse an all-encompassing panpsychism and instead proposes a sort of 'polypsychism' that nonetheless must "balloon beyond all previous limits, but without quite extending to all entities".