Science and Philosophy

Science and Philosophy

H

ugh Everett’s Many Worlds theory (1957) changed my life in a way normally only affected by a religious conversion. Scientific truths can be no less powerful than religious truths. Everett should have a posthumous Nobel Prize, if there is such a thing. David Lewis would have found my attitude puzzling, since he believed that the existence of an infinite number of other worlds, quintillions of which contained our exact counterparts, should make no difference to our lives on this world (On the Plurality of Worlds, 1986, Oxford, Blackwell). Logically, I can accept this, emotionally, I cannot.

            The Many Worlds theory, in which all possibilities are realized, allows for low measure universes, that is, universes of low probability. Ours is surely one of them. This planet should have become a radioactive wasteland during the Cold War and in the majority of universes it is precisely that.

            The idea that there are at least 10>500 identical copies of ‘me’ (Lewis calls them ‘counterparts’), all typing these words together, reminds me of the Buddhist Net of Indra, the Net of Pearls like mirrors, each reflecting all the others. Even as I type, some of these counterparts are dropping dead, going insane or simply not bothering to finish this sentence because they have decided to make love to their wives or mistresses. More prosaically, some pause for a cup of tea or take the dog for a walk. I stubbornly keep on typing. If I suddenly decided to toss a coin and then perform some crazy action like standing on my head and signing the Polish national anthem if it turned up heads, or locking myself in the wardrobe and singing in Welsh if it turned up tails, in what way would the fall of the coin alter the measure of this particular world?

            Some philosophers argue that the existence of an infinity of worlds subverts all ethics. This is untrue. We can be concerned only with the ethics of our own world. Our duty is to ensure that we help to maximise the total good of this world. The rest do not concern us.

            Much of what passes for thinking is no more than speculation. ‘There might be fairies at the bottom of my garden’. There might, but I would have to prove it to myself and to others before I could take this thesis seriously. A thesis must be falsifiable, as Popper says and this one is not falsifiable. Some critics of David Lewis’s brilliant On the Plurality of Worlds, which puts forward a thesis he arrived at through modal realism, not through scientific observation, argue that if this is true then, since there are worlds where we are wrong about almost everything and this may be one of them, we should all be sceptics. In my darker moments I suspect ours may be just such a world.

            The Earl of Kildare was dottily convinced in 1938 that both Serbia and the non-existent Austro-Hungarian Empire would attack Hitler! Since he had a seat in the Lords, he was one of the people running the British Empire. No wonder it did not survive the war. The marvel is that Britain did. Another argument for the Many Worlds theory? In most worlds, a country run by people like Kildare would not have survived. I recall the way in which Britain almost lost WWI because the counterpart Kildares at the Admiralty would not adopt the convoy system until April 1917, when an upstart Welshman, Lloyd George, compelled them to start doing so. In most universes, I suspect we lost the war because Lloyd George was not elected.

            Lewis’s theory advocates “genuine modal realism without overlap, and with qualitative counterpart relations” (On the Plurality of Worlds, 259). I am not so sure about the lack of overlap. It is possible that UFOs come from parallel universes.

            Lewis says we should believe in possible worlds “because the hypothesis is serviceable, and that is a reason to accept it is true” (ibid. 3). Similarly, Paul Dirac used to say that we should accept an equation because it was beautiful and that was a reason to believe it was true. Keats would have agreed with Dirac (Beauty is truth, truth beauty…), Jeremy Bentham with Lewis. I am with Keats and Dirac. It is gratifying to see poetry link hands with mathematics. Empson, a mathematician and a poet, would have enjoyed this.

            The Many Worlds theory exemplifies the Aristotelian principle of plenitude. ‘If a proposition P is possible, then at some time P is true’.  Possible here can be understood in various ways – logically, metaphysically, nomologically, epistemologically, temporally and conceivably. A thing being nomologically possible is the most convincing of these.

            Just as a successful criminal lawyer needs to be something of a crook, so a successful philosopher needs to be something of a cynic. Otherwise, like Mencius, who thought human beings were all born good, he will go wildly astray on the question of human nature. But one has to be cynical to begin with to aspire to become a cynic.  

COPYRIGHT (C) 2010 J D FRODSHAM