What you call the "adjacent possible" is just another way of expressing "the means to the end". What you are saying is that specific ends cannot be brought into existence without the required means to reach that end. Bringing into existence a portion of the required means does not necessitate the end though. It increases the probability of that end. Invention of the microchip did not necessitate the existence of the smartphone, it increased its probability.

But where your description does not seem to be accurate, is that the possibility of the smartphone was still there prior to the invention of the microchip, at a lower probability, requiring the invention of the microchip. So "adjacent possibilities" are not brought into existence by the preliminary invention, they always existed before. The preliminary invention makes the "adjacent possibilities" apprehendable to the human mind.

For one, the idea of the adjacent possible makes it possible (hah) to think of the emergence of possibilities; usually, possibility is thought of as a purely abstract modal category in which certain possibilities are simply either 'realized' or not. — StreetlightX

I think that you have this backward. Bringing something into existence, creating or inventing something actually limits possibilities because any possibility which is excluded by that invention is now denied. What you describe is that bringing into existence something new, allows human beings to apprehend more possibilities. Those possibilities were there before, but not apprehended, as potential ends which require too many means to be apprehended as ends. Knowledge progresses by limiting possibilities, producing impossibilities. This is the nature of certainty, that which is impossible.

In other words, possibility itself can be thought of as indexed to the real, and is not simply 'prior' to it — StreetlightX

This doesn't make any sense to me. Within modality, to be "possible" simply means to obtain in at least one possible world. Given that "emerging possibilities" obviously reference possible ways realities, this doesn't force any changes in how we conceive of modality.

Really, what the philosopher is likely (and correctly) to say is this. There are possible world's which are closer to some world's than others because certain states for affairs are live possibilities for some worlds and not for others, e.g. "It's possible that Bruce Wayne has red hair" is only accessible from worlds in which Bruce Wayne exists. Modal logics have an accessibility relation.

This "adjacent possibility" idea is basically already part of modern discussions of modality.

This "adjacent possibility" idea is basically already part of modern discussions of modality. — MindForged

Well, to put my cards on the table early, I think the whole attempt to cash out possibility in terms of possible worlds is a giant mistake, and that any analytic metaphysics that takes that route is basically a new scholasticism not deserving of being taken seriously. That said - what I find attractive about the notion of the adjacent possible is that it attempts to take seriously the need to account for the individuation of possibility. It does not take the possible as a 'given', simply waiting in the wings to be actualised, even if as a second-order 'non-live' possibility. In the scientific context in which the concept was elaborated, the adjacent possible is created or brought into being where it simply did not 'exist' before hand even qua possible; In Kauffman's own words:

"The ever changing actual “context” of the biosphere constitutes “enabling constraints” that as enabling constraints “create” the Adjacent space of possibilities into which evolution can become. Then that becoming creates a new specific evolutionary situation or context of actual adaptations that again act as enabling constraints creating ever new, typically unprestatable Adjacent Possible directions for evolution." (source [PDF] ).By contrast, possible world semantics is what I see as 'dogmatic' in the properly pejorative, Kantian sense of the term, insofar as it desperately needs something like a Critique of Pure Possibility. Or to put it otherwise, what I like about the adjacent possible is that it provides what I think is another, far superior, scientifically grounded way of thinking about possibility than the idealist logical toys of modern day analytic metaphysicians.

So is the argument something along the lines of
Possibility depends on actuality..
What is actual changes.
Anything that depends on something that changes, itself changes.
Therefore possibility changes?

Or perhaps better
What is possible depends on what is actual.
What is actual changes.
Anything that depends on something that changes, itself changes.
Therefore what is possible changes.

Change "change" for "evolve" if you prefer.

I think ''adjacent possible'' is a very important idea. I can picture it slowly but surely eating its way through the walls of impossibility - that ever so frustating limit one, now only supposedly, can not cross.

In other words, possibility itself can be thought of as indexed to the real, and is not simply 'prior' to it. All of which is to say that the idea of the adjacent possible forces us to revise the very status of modality as classically conceived. Possibility should not simply be thought of as simply pre-existing the real, as though models stowed in a Platonic locker room simply awaiting their realization, but rather, as themselves emerging from the changing configurations of reality itself. Leibniz had a similar approach to possibility in his understanding of 'incompossibility', as did Kant in his advocacy of a 'transcendental logic', but I'll simply mention them as philosophical precedences to the idea outlined above. — StreetlightX

We can know that making a change expands the range of possibilities of additional change, but we can't really know how that will manifest itself. We've discussed emergence vs. reductionism before. The lesson I took is that reductionism is a one-way trip. We can explain higher levels based on lower ones, but we can't predict higher levels based on lower ones. Doesn't that take the wind out of the adjacent possible's sails?

But where your description does not seem to be accurate, is that the possibility of the smartphone was still there prior to the invention of the microchip, at a lower probability, requiring the invention of the microchip. So "adjacent possibilities" are not brought into existence by the preliminary invention, they always existed before. The preliminary invention makes the "adjacent possibilities" apprehendable to the human mind. — Metaphysician Undercover

I don't think this is right. The expanding sphere opens up new possibilities that are not predictable. This shows up every time someone tries to speculate on the world of the future. It's always wrong because the whole system pivots on some little feature no one thought of before or noticed when it happened.

I think the whole attempt to cash out possibility in terms of possible worlds is a giant mistake, and that any analytic metaphysics that takes that route is basically a new scholasticism not deserving of being taken seriously. — StreetlightX

Eh, I can't go that far. Partly, because possible worlds are, as the current history suggests, the impetus behind the resurgence of metaphysics within analytic philosophy. Kripke, that frigging genius, developed it when he was in high school (we should all feel depressed; luckily we can find solace in Kripke's hilariously awful voice).

I mean, even in computer science I basically have to use possible worlds (which in my work I will construe as possible states of a computer), so there's a real boon to using them; I can make recourse to well understood formalisms to make sense (on a logical level) how to describe what I'm doing.

Now of course, there are many semantic & metaphysical views about what possible worlds are that I can't accept or understand (I'm still not sure I understand the position known as "possibilism"), but I don't think I personally would compare them to scholasticism.

attempts to take seriously the need to account for the individuation of possibility. It does not take the possible as a 'given', simply waiting in the wings to be actualised, even if as a second-order 'non-live' possibility. In the scientific context in which the concept was elaborated, the adjacent possible is created or brought into being where it simply did not 'exist' before hand even qua possible

Well I guess I just don't see the upshot of that position. Possibilities are individuated in talk of possible worlds. It's just that some possibilities are only accessible given some other possibilities being the case (e.g. the Bruce Wayne being a redhead example I gave).

Or to put it otherwise, what I like about the adjacent possible is that it provides what I think is another, far superior, scientifically grounded way of thinking about possibility than the idealist logical toys of modern day analytic metaphysicians. — StreetlightX

What does it provide that is superior? From the Kauffman quote, he seems to be using essentially the same idea of modality as I'm familiar with:

that as enabling constraints “create” the Adjacent space of possibilities into which evolution can become. — Kauffman

This is exactly what I understand worlds being "more accessible" to other worlds to mean in Possible Worlds Semantics. Certain possibilities open up a space of other possibilities which would otherwise not be adjacent to them, to use Kauffman's terminology.

The discussions we've had about reductionism and emergence in the context of the development of life are my favorites here on the forum. These ideas say profound things about the way our world works. Because of that, they also say profound things about what knowledge and existence are.

Well, to put my cards on the table early, I think the whole attempt to cash out possibility in terms of possible worlds is a giant mistake, and that any analytic metaphysics that takes that route is basically a new scholasticism not deserving of being taken seriously. — StreetlightX

But that guy said we all have perfect boyfriends/girlfriends; husbands/wives in some possible world. He even says we can write letters to them? If he's wrong, then I'm a complete loser feeb. That can't possibly be true.

I don't think the OP is pointing out anything particularly deep. Once you fry an egg the raw egg can't be gotten from it. Similarly, you can't make a fried egg sandwich without frying the egg. Obvious check towards @apokrisis here regarding dichotomies and constraints and the arrow of time induced by irreversible processes.

You could of course model that with a poset accessibility relation producing a linearly ordered series of worlds; like a flow chart for making a fried egg sandwich. But...




I read that the difference between the adjacent possibility in the OP and the adjacent possible being the nearest neighbours of an index world in the graph of an accessibility relation is that the possible is internalised to the world. It's the difference between 'this rock falls in some possible world' as a sense of possibility for the rock falling vs 'this rock has the potential energy to fall'. More precisely, the sense of possibility potential energy imbues to the rock vs the sense of possibility of it starting to fall in a nearby possible world.

I think there's also an implication that the potential-sense of possibility for rock falling is logically prior to the possible-world sense of possibility for rock falling, the latter would be said on the basis of the former. Adjacent possibility (potential being constrained by the actual) being the condition for the possibility (lulz) of substantive possibility (contingent truth or falsehood turning on holding in a possible world).

Well I guess I just don't see the upshot of that position. Possibilities are individuated in talk of possible worlds. It's just that some possibilities are only accessible given some other possibilities being the case (e.g. the Bruce Wayne being a redhead example I gave). — MindForged

A brief response to this as I'm about to hit the sack: part of what I want to do is suck the explanatory air put of possibility-talk altogether; possibility is what must be accounted for, and is not what ought to do the accounting. @Fdrake is on the money here:

the potential-sense of possibility for rock falling is logically prior to the possible-world sense of possibility for rock falling, the latter would be said on the basis of the former. Adjacent possibility (potential being constrained by the actual) being the condition for the possibility (lulz) of substantive possibility (contingent truth or falsehood turning on holding in a possible world). — fdrake

Possible-worlds talk is always ex post facto, what Bergson called the retrograde movement of the true.

. The lesson I took is that reductionism is a one-way trip. We can explain higher levels based on lower ones, but we can't predict higher levels based on lower ones. Doesn't that take the wind out of the adjacent possible's sails? — T Clark

Au contrarie, the idea is that the adjacent possible takes the wind out of reductionist sails. The Kauffman paper I linked to is not for nothing titled "Beyond Reductionism Twice".

Au contrarie, the idea is that the adjacent possible takes the wind out of reductionist sails. The Kauffman paper I linked to is not for nothing titled "Beyond Reductionism Twice". — StreetlightX

I downloaded the paper.

possible is internalised to the world — fdrake

I think in that case you're talking about physical possibility, whereas I was referring to metaphysical possibility. And besides, even in that example, I don't see the issue. The actual world is part of the set of possible worlds. So a rock having the potential energy to fall can be said to be possible within that world itself. After all, nearly every accessibility relation of nearly any modal logic will imbue give that relation a the reflexive property; worlds can access themselves.

Reflexivity of the accessibility relation just says that the actual world (whatever that is) is always a possible world (whatever that is). So:

So a rock having the potential energy to fall can be said to be possible within that world itself.

yes of course. The possible worlds of various counterfactual states of the falling rock are generated by how it could fall. Collapsing the sense of that could to simply be worlds which differ counterfactually gives only an extensional definition of the could without the means that the terms in that extensional definition were paired to it.

You could say the same of any possible world, actuality becomes just an indexical property if its sense is equated with the reflexivity of an accessibility relation.

There's a rejoinder I've seen before about a hierarchy of possibility senses:

physical possibility < metaphysical possibility < logical possibility

I think the OP's operating from a perspective from where giving an account of physical possibility is a healthy part of the metaphysics of this world rather than treating 'the metaphysical', whatever that is, as some indeterminate excess of the physical (whatever that is) - with usual examples of 'laws with changed physical constants' or (arguably) p-zombies.

Isn't it more interesting to try to give a good account of how potential and actuality relate as concepts and realities than a deflationary account of both in terms of possible world semantics?

Sunflowers and mosquitoes and brains exist outside that circle of possibility." The idea of course is that they can be brought inside that circle of possibility after a certain level of evolutionary achievement has been reached — StreetlightX

I propose a name for that realm outside the circle of possibility - 'the circle of the fantastic'. It seems to me that myth and fairytale have explored this un-possible world, and civilisation is the process of realising the fantasies, from Mercury's winged Virgin sandals to Thor's intercontinental ballistic hammer. One facebook to rule them all, and in the darkness bind them.

There are really two stories here. Kauffman originally came up with the adjacent possible as a law of life and complexity. So it has a semiotic twist.

Once an organism masters a particular constructive act, then that opens up some new space of possible things it could construct. So it is about how evolution can get going once there is a source of requisite variety. Once you can make proteins, all sorts of protein based innovation becomes evolvable.

But the ordinary physical world is simpler, less semiotic. It is just a set of historical constraints that have locked in the accidents of the past and shaping the possible range of accidents in the future as the whole world rolls down its thermal gradient as a developing field of meaningless accidents.

So the physical world produces complication rather than complexity. It blindly develops as dissipative structure, where life and mind are about the invention of construction and the new constraint of evolutionary selection that goes with that.

I remember Kauffman pushing the adjacent possible in a quantum context, so he did stray beyond his initial point. But it seemed one his less impressive moves (and generally I really like his stuff). I think it reflects the fact that the Santa Fe brand of complexity lacked the clarity of more semiotic approaches (like Rosen, Salthe and Pattee). DST had the same problem. The dynamicists tended to blur the line to make everything a simple story of constraints and self-organisation. But for life and mind, the fact of memories, codes and algorithms have to be included as the part of the story that doesn’t reduce to the physics.

So the adjacent possible was a weak idea in not highlighting the difference between the increasing negentropic possibilities of complex construction and the diminishing thermal possibilities of simple dissipation.

don't think this is right. The expanding sphere opens up new possibilities that are not predictable. This shows up every time someone tries to speculate on the world of the future. It's always wrong because the whole system pivots on some little feature no one thought of before or noticed when it happened. — T Clark

But a possibility does not need to be predicted, or even to be apprehended in order to exist as a possibility. After it is apprehended it exists as an apprehended possibility. So the "expanding sphere", if this refers to the sphere of what is apprehended, does not open up new possibilities, it just the apprehension of possibilities which were previously not apprehended. And if "expanding sphere" refers to the creation of new physical realities, this does not create new possibilities, they were already there as possibilities which required the expanding sphere in order to be actualized.

In the scientific context in which the concept was elaborated, the adjacent possible is created or brought into being where it simply did not 'exist' before hand even qua possible; In Kauffman's own words: — StreetlightX

This is a mistaken idea. The possibility always "existed", it is just one step closer to becoming a reality. Most possibilities require numerous efficient causes to be brought into reality. Each efficient cause which is fulfilled brings the possibility closer to reality. But it is wrong to say that fulfilment of one or another of the efficient causes brings the possibility into existence.

Once you fry an egg the raw egg can't be gotten from it. — fdrake

That's the point I made, creating something produces impossibilities, not possibilities. It eliminates the possibilities which the creation of that thing excludes.

Reflexivity of the accessibility relation just says that the actual world (whatever that is) is always a possible world (whatever that is). So: — fdrake

That's basically what I said. If worlds couldn't access themselves then they wouldn't be a live possibility... with respect to themselves!

You could say the same of any possible world, actuality becomes just an indexical property if its sense is equated with the reflexivity of an accessibility relation. — fdrake

I don't think I equated actuality with reflexivity, I brought that up when I was trying to think of what else you might have meant by "possibility in this world" Besides physical possibility. I think only on a modal realist's account is actuality just an indexical property. Arguably, that is a really attractive view in how to define actuality, though the rest of the theory is a bit... much.

physical possibility < metaphysical possibility < logical possibility — fdrake

I've often seen this, but I'm always struck by how odd the last two are. Much of the time, metaphysical possibility/necessity are cashed out in terms of logic. That is, X being consistent is necessary and sufficient for being metaphysically possible, being a logical truth is necessary and sufficient for metaphysical necessity, and impossibility is for the contradictions. It makes those two modalities seem to be synonyms. At the risk of bringing this thread too far of course, how do you differentiate metaphysical and logical modalities?

I tend to think of logical modalities as a sort statement about a particular logical formalism, e.g. P & ~P => Q is logically necessary in Classical Logic. Giving them too much metaphysical baggage seems to result in odd questions like, what's the metaphysical analogue of these laws? In the logic, it seems like the rules I establish as valid, and I can do all sorts of manipulations that have no metaphysical equivalent (like deploying a contradiction).

I propose a name for that realm outside the circle of possibility - 'the circle of the fantastic'. — unenlightened

I prefer the more mundane 'impossible'. It interests me too because in political theory there is an approach to understanding proper political action as that which aims to bring about the impossible: that is, to change the very distribution of the possible such that what was once deemed impossible is rendered otherwise through acts of political courage. To demand the impossible: the basic definition of a politics worthy of the name. So another advantage of thinking about the adjacent possible as a ever-moving horizon of possibility.

I like the idea. I want to say it opens a space for the 'art of the possible' - jettison the possible worlds stuff (which, to my limited understanding, seems fine and useful, long as it recognizes it limits and doesnt try and reify formal analysis) but jettison that, and you have a space where an aesthetic (or social) eye can pick out new avenues. I can't play music myself, but I have enough friends who can, where if I'm able to vibe out and listen, you can *feel* when someone has picked up on some potential and starts to bring it into fruition. so satisfying. I know this is all vibes and aesthetics, but its really not subjective. it only 'works' if the potential was there. The 'there' is complex. it's the music, but also the people, and the setting. So more like politics than biology. but maybe the same basic idea.

Possibilities are individuated in talk of possible worlds. — MindForged

To come back to this: they really aren't. There's no actual individuation that goes on at all: the whole idea is that possible worlds are a given set out of which the actual world is simply one; as you said, "the actual world is part of the set of possible worlds". But one is hard pressed to come up with a more stupid account of individuation: "well it is possible because it is possible that it is possible (and we've invented some rules regarding this!)". One wants to say to the whole enterprise of modal semantics: fuck off.

But in all seriousness, in the background here is Bergson's critique of possibility: for Bergson, the very idea that there are individual possible entities (whether 'worlds' or events or whathaveyou) is something of a mere grammar mistake. It used to be that to say that something was possible was just to say that it was not impossible. "We can do the thing" (given the current conditions). But then some idiots decided that it'd be a good idea to reify individual possibilities as quasi-substantial entities in-themselves. So where possibility once designated a mere truism ("it is not impossible"), it began to taken on a positive sense which Bergson refers to as "pre-existence under the form of the idea". But for Bergson, this approach to possibility is thoroughly parasitic or derivative of actual things. As he says, there is in fact 'more' in the idea of the possible than there is in the idea of the actual:

"But there is especially the idea that the possible is less than the real, and that, for that reason, the possibility of things precedes their existence. They would thus be representable in advance; they could be thought before being realized. But it is the inverse that is the truth... For the possible is nothing else than the real with, in addition, an act of the mind which casts the image of it back into the past once it comes forth... Just to the extent that reality creates itself, unforeseeable and new, its image reflects itself behind itself into the indefinite past; thus it finds itself to have been possible at all times, and that is why I said that its possibility, which does not precede its reality, will have preceded it once the reality appears. The possible is thus the mirage of the present in the past." (Bergson, Creative Evolution).

So the positive sense of possibilities pre-existing the real is basically a retroactive illusion based on nothing more than a mistake of grammar. The entirety of PWS is bad grammar, and everyone who works on it should go back to elementary school and learn some proper english before engaging in metaphysics. So while it's always 'possible' (not-impossible!) to ratiocinate and say things like "So a rock having the potential energy to fall can be said to be possible within that world itself", the whole recasting of potentiality into possible worlds and accessibility relations is entirely parasitic act that takes for granted the very thing it attempts to account for. (Hence fdrake: "The possible worlds of various counterfactual states of the falling rock are generated by how it could fall').

That's basically what I said. If worlds couldn't access themselves then they wouldn't be a live possibility... with respect to themselves! — MindForged

Yeah, was rephrasing what you said to show we're on the same page.

I don't think I equated actuality with reflexivity, I brought that up when I was trying to think of what else you might have meant by "possibility in this world" Besides physical possibility. I think only on a modal realist's account is actuality just an indexical property. Arguably, that is a really attractive view in how to define actuality, though the rest of the theory is a bit... much. — MindForged

Do you think that the potential energy the rock we've been talking about has isn't actual - part of this world?

But there is especially the idea that the possible is less than the real, and that, for that reason, the possibility of things precedes their existence. They would thus be representable in advance; they could be thought before being realized. But it is the inverse that is the truth... — StreetlightX

I disagree with Bergson. Flying was dreamed of while it was impossible; seven league boots were dreamed when a horse was the limit of travel. What you want to call the impossible, or the not yet possible is represented in advance. I agree about politics - the only politics worth considering starts with "I have a dream..."

The business of the engineer and the architect is to concoct a realisable dream, to represent pre-present in plans and specifications the adjacent possible. The business of poets and shamans is to have more foresight and pre-present the impossible.

Flying was dreamed of while it was impossible — unenlightened

Clearly it wasn't.

In any case the "dreams of possibilities" have nothing to do with possibility as a modality. One can dream all one likes. To confuse the two is grammatical equivocation.

the return of Magic....!

Clearly it wasn't. — StreetlightX

Mercury, Pegasus, Daedalus, witches... to name but a few. And it's not equivocation; nature is blind to everything but the immediate, but human history simply is the realisation of fantasy under the guise of 'planning'.

Oh is that what it was about? The Sorcerer's Apprentice with his broomstick robots - a warning from mythology.

Mercury, Pegasus, Daedalus, witches... to name but a few. And it's not equivocation; nature is blind to everything but the immediate, but human history simply is the realisation of fantasy under the guise of 'planning'. — unenlightened

Fantasy <> possibility. If you want to modalize fantasy, go ahead, but don't pretend it's philosophy.