Earman, John (1942–)

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EARMAN, JOHN
(1942–)

John Earman is an American philosopher and professor of history and philosophy of science at the University of Pittsburgh. He is perhaps best known for contributions to the history and foundations of modern physics—especially space-time theories, and often with the question of determinism in view—and confirmation theory.

Earman completed his PhD at Princeton in 1968, under the direction of Carl G. Hempel. After brief appointments at University of California, Los Angeles, and the Rockefeller University, where he enjoyed tenure for a year before its philosophy department was disbanded in 1973, Earman spent twelve years at the University of Minnesota, where he was promoted to full professor in 1974. He moved to Pittsburgh in 1985.

Spacetime and Determinism

A theme of Earman's earliest publications is that progress can be made on perennial philosophical problems by bringing modern physics and mathematics, thoroughly and properly understood, to bear on them. Through the late 1960s the reigning orthodoxy in the philosophy of space and time held the dispute between absolute and relational accounts to have been settled conclusively, and in favor of the relationalist, by the advent of relativity theory. Presenting Albert Einstein's theory in the language of differential geometry—the mode of presentation favored by mathematical physicists—Earman argues persuasively, in "Who's Afraid of Absolute Space" (1970), that traditional terms of debate are hopelessly ambiguous. The scientifically respectable disambiguations he devises enable him to turn orthodoxy on its head. Isaac Newton's arguments for absolute space succeed, Earman contends, and absolute kinematic quantities abound in relativistic space-times. Along with the contributions of Howard Stein, Michael Friedman, and Larry Sklar, this work helped drag the philosophy of space and time into its modern era.

As Earman aged, he aimed less to resolve perennial philosophical problems than to deploy them as a sort of dragnet in which to ensnare important issues in the foundations of physics. The philosophical problems typically emerge from this deployment considerably complicated. A Primer on Determinism (1986), which won the Lakatos Prize in 1989, recasts the question of whether the world is deterministic as a question about whether there are other physically possible worlds—that is, other worlds obeying the same natural laws as the actual world does—that agree with the actual world at some times but not others. Subsequent chapters subject the doctrine of determinism to trial by a variety of prominent theories. Surprising verdicts are reached: Earman declares classical Newtonian mechanics, the physics that inspired Pierre Simon de Laplace's chilling statement of determinism, indeterministic. Admitting infinite signal velocities, classical physics admits as well possible worlds that agree up to a time t, but differ afterward due to the unheralded arrival at t in one world but not the other of "space invaders" that have traveled infinitely fast from spatial infinity. More often, the jury is hung and the fate of determinism is entangled with "sticky interpretations problems [that] resist narrowly scientific solutions" (p. 197). "We can't just read off the lessons for determinism from various branches of physics, for the implications we read will depend upon judgments about the adequacy of physical theories, and those judgments will depend in turn on our views about determinism" (p. 78).

In World Enough and Space-Time: Absolute versus Relational Theories of Space and Time (1989) determinism probes the doctrine of absolute space Earman so energetically rescued from ill repute in the 1970s. Space-time substantivalism—the thesis that spatiotemporal relations between bodies are "parasitic on relations among a substratum of … spacetime points that underlie events" (p. 12)—is a modernization of the doctrine with an impeccable pedigree: Newton himself, Earman argues, was a substantivalist. But Earman is not. He takes the lesson of Einstein's hole argument to be that anyone committed to substantivalism about general relativistic space-times is also committed to indeterminism (compare Earman and Norton 1987). On the principle that "if determinism fails, it should fail for a reason of physics" (Earman 1989, p. 181), Earman rejects substantivalism. He does not thereby embrace relationalism: "[M]y tentative conclusion is that a correct account of space and time may lie outside the ambit of the traditional absolute-relational controversy" (p. 4). The sample tertium quid he sketches—an interpretation mediated by Leibniz algebras—was later shown itself to imply indeterminism (Rynasiewicz 1992).

The hole argument turns on the fact that if one of any pair of space-times related by a hole diffeomorphism —roughly, a map between space-times that is the identity outside a region h (the hole) but is nontrivial inside that region—corresponds to a world possible according to general relativity, then so does the other. Supposing that substantivalists must take space-times related by a hole diffeomorphism to differ in properties assigned space-time points inside h, Earman and Norton (1987) conclude that substantivalists must take there to be worlds possible according to general relativity that agree at some times but not others. The hole argument launched a thousand responses. Many philosophers took exception to its accounts of reference to, or criteria for transworld identity of, space-time points, while some physicists credited the hole argument for raising interpretive questions pertinent to ongoing efforts to quantize gravity.

One way determinism might fail for a reason of (general relativistic) physics arises from space-time singularities. Space-time singularities are, roughly speaking, regions of space-time at which Einstein's equations become mathematically ill defined, so that imposing those equations is insufficient to prevent determinism-destroying emanations—Earman seems particularly worried about televisions playing Richard Nixon's "Checkers" speech—from those regions. Bangs, Crunches, Whimpers, and Shrieks: Singularities and Acausalities in Relativistic Spacetimes (1995) discusses singularities and other eponymous acausalities. The book's topics—chronology horizons, inflationary cosmologies, and cosmic censorship—familiar to working physicists but less evidenced in philosophy journals, reflects a tendency, appearing in the mid-1980s and accelerating thereafter, for Earman to draw his problem agenda directly from contemporary physics.

Bayesian Confirmation Theory

The first half of Earman's Bayes or Bust?: A Critical Examination of Bayesian Confirmation Theory (1992) skillfully surveys the grounds supporting Bayesian confirmation theory: for example, the perspicuity of the analyses it offers of other accounts of confirmation, and its ability to provide some sort of solution to the Quine-Duhem problem and the new riddles of induction. The second half ruthlessly undermines those grounds, for example, it finds Bayesianism incapable of addressing the problem of old evidence or accommodating changes of belief in so-called scientific revolutions. Characteristically, Earman considers the point of the exercise not to reach a verdict on Bayesianism—in the introduction he admits to a diurnal oscillation between being an "imperialistic apostle" of Bayesianism and doubting its very viability—but to uncover worthwhile problems in the course of weighing the evidence.

These problems include historical ones—how to understand Thomas Bayes's essay in the context of eighteenth-century work on probability, for example. A concern, and a knack, for matters historical informs much of Earman's work. Hume's Abject Failure: The Argument against Miracles (2000), his most recent book, situates David Hume's argument against miracles in a historical context. That Bayes and Hume were contemporaries licenses Earman to develop Bayesian analyses of Hume's central contentions and the notions (e.g., multiple witnessing) they involve. Although Hume's Abject Failure was not universally well received by Hume scholars or philosophers of religion, some of whom charged it with insensitivity to Hume's broader epistemology and with harboring too many equations, the work accomplishes its self-described aim: "not simply to bash Hume … but also to indicate how, given the proper tools, some advance can be made on these problems" (p. 4).

Bibliography

Earman, John, and J. Norton. "What Price Space-Time Substantivalism? The Hole Story." British Journal for the Philosophy of Science 38 (1987): 512–525

Rynasiewicz, Robert. "Rings, Holes, and Substantivalism: On the Program of Leibniz Algebras." Philosophy of Science 59 (1992): 572–589.