Thursday, March 17, 2011

David K. Lewis' "On The Plurality of Worlds": A Summary

If you picked up this book thinking a 'plurality' means, like, 7, then buckle the fuck up, kids.

Think of all the ways things could have been. The mundane ways, sure: you could have preferred tea instead of coffee, that lightbulb could have been blue instead of yellow, Steve Jobs could have founded Windows. Whatever. But shit could have been way crazier than that. We could have tentacles. Gravity could have been twice as strong. Geometry could be parabolic. Electrons could be replaced with - who the fuck knows, really. 

Are you ready for the fun part? Because here comes the fun part: there are uncountably infinitely many worlds, and there's a world for every single fucking possibility. Remember how Hume said that nothing was ever necessarily connected to anything else? Yeah. As long as something doesn't contain any blatant contradictions, there is a world in which it's reality. 

Of course, we can't get to these worlds, otherwise they'd be part of our world; they're completely isolated from our world in every way. "But surely our world is the real world?'' Fuck you. They're all real. You're not special and neither is your world - I have no clue what it would be like for them to be 'imaginary.' The only world I have any experience of is this one, and it's as real and concrete as can be. I bet they are too.

Look, I get it. You're, ah, incredulous - believe there are infinitely, uncountably many worlds as real as the world I'm in? At first, it sounds a little crazy. Except that - and here's the thing - it cuts through problems like a fucking scythe. Possibility and necessity? Fucking cake. If you want to know what's physically possible, just take every world where physics is the same as ours. If you want to know what's historically possible, just take every world with the same history as ours right up to whenever you have the question. Biology, chemistry, geometry, whatever. The problem of universal properties? Just the set of all things with that property in any world. Counterfactuals? Just look at the world most similar to ours where the antecedent is true. BOOM. Seriously, I can do this all fucking day.

So yeah, I happen to believe in a bunch of things. No, I can't prove their existence. But think of all the shit that you believe in without proof - 'redness'? 'Propositions'? Possible, imaginary worlds where, somehow as if by magic, Socrates isn't an ugly motherfucker? Even sets seem questionable - how could there be some universal object that contains all and only the odd numbers? But sets are useful as fuck, so we deal with them. Well, I say if you're going to make shit up, GO BIG OR GO HOME, bitches. If you think it's too crazy, whatever bro - not everyone is worthy. But don't come in my house, kick my dog, and tell me you have a simpler solution that you just made up where everything magically makes sense because your hand-waving said so. Mind tricks do not work on me, only ontologies.

So while you slave away trying to simplify your beliefs or build worlds out of words, as if coins can be minted by calling gold 'round', I'll be here with my sets and my concrete objects, solving everything and being awesome. Don't look at me like that - I'm right and you know it.


Get On the Plurality of Worlds on Amazon. Unless, that is, you're already a professor or a grad student, in which case your already thrice-highlighted and oft-consulted copy will do just fine.


  1. If Lewis is right, we're all in a sense immortal:

    Of course, it seems to me that if he's right, the only thing stopping Anselm's argument for the existence of God being true would be his claim that there's no way to cross from one possible world to another.


  2. Wm:

    In that comic Lewis is responding to a different many-worlds interpretation - he would put quantum many-worlds into a single concrete world, if they're true.

    Also, he famously said that "in a sense, I'm the most extensive polythiest in history" - he has infinitely many worlds in which a 'god' of some sort exists, but none of them transcends its world.

  3. "If you want to know what's physically possible, just take every world where physics is the same as ours."

    I'm angry. You should clarify this further; it's not necessarily true that ours is the only set of physical laws that supports life/etc.

    Of course, I could be missing your point entirely.

  4. Great reason to avoid analytic philosophy. Ever read any Levinas? Doooooo ittttt.

  5. @Ranter. He wasn't saying that our physical laws are the only ones that can support life. What he is saying is that if we look at all of the possible worlds where physics is the same then we can see all of the possible outcomes that could occur in our own world. Since we can only see one outcome in our own world we would need to look at other worlds to see what else could happen. Does that make more sense?

  6. Great post, Bro.

    I don't see why a seriously committed philosopher/philosophy student couldn't read both Lewis and Levinas. They both have much to offer. Lewis' most important works are in his Collected Papers Vols. I & II. "Attitdues de Dicto and de Se" is an incredible piece of philosophy. "Psychophysical and Theoretical Identifications" changed my life--seriously. The method through which he addresses functionalism (called "analytic functionalism" in contrast to "machine" or Turing style functionalism) *taught* me about creative, innovative approaches to philosophical problems. Read Lewis and see what one can learn.

    Having great teachers in a department capable of covering the best works in "continental" an "analytic" philosophy really helps. But students of philosophy should realize that this "war" is totally early 90's, and pretty much over. It does no good to demonize different philosophical methodologies at this point. If there's good philosophy, stand on that. Don't drink expired Kool Aid.

  7. You, my man, are doing the Lord's work.

  8. Wm, can you clarify what the fuck this has to do with Anselm's argument? Not seeing the connection...not to mention the Ontological argument is generally one of the stupidest pieces of philosophy I've ever read.

  9. Simplicity, bro. Simplicity. Scythes are for dough boys who run toy trains in their basements.

  10. This paper by David Lewis is about the philosophical topic of "ontology", which is the field of philosophy that deals with asking what kinds of things exist. Anselm's argument is called the Ontological argument for the existence of God because he is positing that there is a necessary condition about existence itself that guarantees God's existence. It is, in my humble opinion, one of the most clever and brilliant works of analytical philosophy in known history. And that's coming from an atheist, bro.