Why Does the World Exist?: An Existential Detective Story by Jim Holt Read Free Book Online

and American philosophers jointly pioneered what has become known as the “subtraction argument.” Unlike the observer and container arguments, which were anti-nothingness, the subtraction argument is pro-nothingness. It is meant to demonstrate that an absolute void is a genuine metaphysical possibility.
    The subtraction argument begins by assuming, plausibly enough, that the world contains a finite number of objects—people, tables, chairs, rocks, and so forth. It also assumes that each of these objects is contingent : although the object does in fact exist, it might not have existed. This too seems plausible. Think of the movie It’s a Wonderful Life , and its protagonist George Bailey (played by Jimmy Stewart). After a series of setbacks in his life, George finds himself contemplating suicide. Thanks to the intervention of an angel named Clarence, George gets to see what the world would have looked like if he had never been born. He is confronted with the contingency of his own existence. The same contingency seems to infect not only individual people, but also the entire inventory of actually existing things, from the Milky Way to the Eiffel Tower to the dog sleeping on your sofa to the speck of dust on the mousepad of your laptop. Each of these things, although it happens to exist, might not have existed if the cosmos had unfolded differently. Finally, the subtraction argument makes an assumption of independence : that the nonexistence of one thing does not necessitate the existence of anything else.
    With all three of these premises in place—finiteness, contingency, and independence—it is easy to derive the conclusion that there might have been nothing at all. You simply subtract each contingent object from the world, one by one, until you end up with absolute emptiness, a pure void. This “subtraction” is supposed to be metaphorical rather than literal. Each stage of the argument asserts a relationship between possible worlds: if a world with n objects is possible, then a world with n− 1 objects is also possible. At the penultimate stage in the subtraction process, the world might consist of no more than a single grain of sand. If such a sad little world is possible, then so is a world where that grain of sand is deleted—a world of nothingness.
    The subtraction argument is generally considered to be the strongest one in the arsenal of the metaphysical nihilists. Indeed, it may be the only positive argument they have. Although I have stated the argument somewhat crudely, its proponents have painstakingly put it into a form where it appears to be logically valid: no mean feat. If the premises are true, the conclusion—that absolute nothingness is possible—must also be true.
    But are the premises of the subtraction argument true? In other words, is the argument not merely valid, but also (as logicians say) sound ?
    Well, the finiteness and contingency premises seem okay. But the third premise, that of independence, is more dubious. Can we really be sure that the nonexistence of one thing does not entail the existence of something else? Think again of It’s a Wonderful Life . In the alternative world where George Bailey never existed, many other possible things did exist as a consequence—like the sleazy bars and pawnshops of “Pottersville,” which the greedy banker Mr. Potter would have created had decent George not been around to stop him. Contingent things are not so independent after all. Each thing, no matter how shaky its own claim to existence, seems implicated in a web of ontic interdependency with many other things, both actual and possible.
    If a cinematic example is too fanciful for you, consider a more austere, scientific one. Suppose the world consisted of just two objects, an electron and a positron in mutual orbit. Relative to this “pair world,” is there a possible “singleton world” in which only the positron exists? One might think so. But the move from the pair world to the