Often in debates about emergence, an opposition is set up between (strong) emergence and reductionism. These are seen as incompatible alternatives.

In particular, if one believes in downward causation, or perhaps some kind of non-causal influence (emanationism ) going from higher-level to lower-level phenomena, then, in the usual framing of the discussion, this is seen as contradicting scientific reductionism, which holds that the causal interactions within the lowest level totally causally determine the behaiviour of the higher level. (Whether or not we can predict the behaivour at the higher-level from the lower-level is a separate question.)

However, I've often wondered if there could be a view analogous to compatibilism in the free will debate which attempts to affirm both strong emergence and causal reductionism.

We can consider how that might go by considering Conway's Game of Life. In this game, there are certain apparently emergent structures such as gliders which move across the grid and seem to have various effects on other structures that they locally interact with. However, in this case, there is also an obvious sense in which causal reductionism is true since we know from how the game is build that deterministic rules governing sequential updates to individual pixels generate all the observed behavior.

Nevertheless, one could deny that gliders and other game of life structures are merely epiphenomenal. A neo-Platonist might hold that these structures are emanations of Forms in a higher level of existence and this claim would not have to contradict the claim that, at the material level, their behavior is causally determined by the pixels and update rules.

Of course, the details of such a view are vague, and I'm not attempting to defend it here. My question is whether there are any articulate modern defenders of something like this. I guess I would call it non-causal or emanationist strong emergence (although it might have a totally different name in the literature).

As an aside, if such view of emergence is viable, then a form of compatibilism about free will might end up being a special case of this type of emergence. This is hinted at in Stephen Wolfram's discussion of cellular automata and free will in A New Kind of Science.

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    "Top down causation" is a term commonly used in biology to describe environmental effects on an organism at cell level. But it is "compatibilist" exactly because it is not an example of strong emergence, neither is Game of Life, see Top-down causation without top-down causes:"The relationship is not a causal relationship... Mechanistically mediated effects are hybrids of constitutive and causal relations in a mechanism, where the constitutive relations are interlevel, and the causal relations are exclusively intralevel."
    – Conifold
    Aug 13, 2022 at 0:30
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    This just sounds like epiphenomenalism as discussed in a recent post: These results have been interpreted to suggest that people are capable of action before conscious experience of the decision to act occurs. Some argue that this supports epiphenomenalism, since it shows that the feeling of making a decision to act is actually an epiphenomenon; the action happens before the decision, so the decision did not cause the action to occur... Aug 13, 2022 at 2:45
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    Nevertheless, one could deny that gliders and other game of life structures are merely epiphenomenal. A neo-Platonist might hold that these structures are emanations of Forms in a higher level of existence and this claim would not have to contradict the claim that, at the material level, their behavior is causally determined by the pixels and update rules. I think this idea is completely relevant, and I choose to call it "middle emergence". It's not strong emergence, because there's no downward causal force, but the emergent "stuff" still has some kind of ontological realness to it.
    – TKoL
    Nov 14, 2023 at 12:18
  • @TKoL I recently came across an account of a form of middle emergence that you might like. It is presented in Erik Hoel's recent book, The World Behind the World (Chapters 10 and 11). He uses causal graphs to argue compellingly for a notion of "causal emergence" that is neither reducible nor extra-physical. In Chapter 11 he picks up on some theme's from Wolfram's ANKOS to argue for free will on the basis of causal emergence.
    – Avi C
    Feb 11 at 23:36
  • @AviC thank you, very interesting. Is his view that this middle-emergent stuff is still at some level causally sourced in the lower-level stuff? As in, the lower-level stuff can always follow lower-level rules, and the higher level stuff emerges from it naturally?
    – TKoL
    Feb 12 at 9:47

1 Answer 1


Weak emergence is the thesis that discussing emergent phenomenon is just a useful shorthand to deal with higher level phenomena that are presumed to be reducible in principle but are not yet reduced. A slight modification of weak emergence is that we may have a permanent inability through lack of time or sufficiently accurate sensors to ever be able to reduce all higher-level phenomenon, but this is a practical, not a logical obstacle. Weak emergence is compatibilist with reductionism.

Strong emergence holds that higher level phenomena are NOT reducible to lower level, as a logic principle. As such, it is intrinsically not compatibilist with reductionism. The two aspects to this that have convinced scientists of strong emergence are the unpredictable discoveries of phase changes, and the discovery of multiple realizability within functionalism -- that there are phenomena that DO NOT CARE what substrate they are based on.

The viewpoint that science has adopted, is that of pluralism. IE, that there are valid sciences that study other fields than physics, and NONE OF THESE ARE REDUCIBLE TO OR DEPENDENT ON PHYSICS. Under pluralism, these sciences, and the phenomena they study, have the same truth-validity as physics. They are all equally based on Popperian usefullness of the predictive models.

Pluralism has spread well beyond science. Non-scientists have been insisting for most of a century that scientism is false -- that science is not the only valid way to gain true knowledge of our world. History, art, art criticism, pragmatic skills like fletching, all are valid knowledge sources to those not asserting scientism. The fraction of thinkers who think scientism is valid, has shrunk to a handful, and scientism is now based on the premise that scientists themselves are wrong about scientism. Note that in science, the arbiter of truth of an empirical inference is the ability to convince a consensus of ones peers, so scientism is currently anti-science.

For a good discussion of reductionism, and its recent abandonment within the philosophy of science, see the SEP article, particularly section 5. https://plato.stanford.edu/entries/scientific-reduction/

Pluralism is a DIFFERENT viewpoint than non-reductive physicalism. NR physicalism holds that higher tier phenomena may not be reducible to lower tier, but they must be entirely dependent and constrained somehow. IE there are two tiers of validity for scientific inference to reality, and while non-physics inference is VALID, and those phenomena are real, they are also logically dependent on physics. So physics is MORE real. How this constraint/dependence works, is still unknown and TBD, as we really have no idea how emergence works.

The validity of Popperian inference is not field-of-study dependent, so NR physicalists may be claiming there should be some other criteria for our "true" knowledge. OR, they might be speculating about what study of and understanding of emergence will eventually show. NR physicalism can also accept non-science knowledge is valid, so it isn't a revival of full on scientism. I think you may be looking for a fleshed out explanation of non-reductive physicalism. I have not seen such a discussion, but have not done the search of this field to see if anyone has done this fleshing out. I hope this commentary will give you the hooks to do your own search.

  • Thanks for the detailed answer. I'm left wondering how to map these positions to the Conway Game of Life example. The closest thing in what you wrote was functionalism, but you didn't got into much detail about that. It sound to me that functionalism is actually a kind of Platonism in which abstract entities ("functions") non-causally constrain the evolution of systems that instantiate them. In that case, we could see the glider in game of life as a realization of a "function". (Function is an odd choice of terminology here in my opinion but I'm sure there are historical reasons).
    – Avi C
    Aug 29, 2022 at 2:22
  • I consider Functionalism to be a version of platonic dualism, in which Functions are causal on matter and vice versa, AND there is an Identity Theory relation between functions and consciousness. Most functionalists however identify themselves as physicalists, so this question is in dispute. Game of Life looks to me to be an example of pure weak emergence. Its "objects" I think are just arbitrary assignments by we the observer, not actual objects that "cut the universe at its joints", in the words of Plato. But then, I have no interest in Game of Life, as I think it irrelevant.
    – Dcleve
    Aug 29, 2022 at 3:48
  • Game of Life is an artificial system but the point is the same if you consider naturally occuring examples of complex dynamical systems with behavior determined by local causal interactions which neverless displays higher level (holistic) properties that feedback and constrain the evolution of the system. I'm not sure causation is the right category for this, but I think we reach for it because we don't have a good vocabulary for non-causal types of influence. The Neo-Platonists used the term "emmanation" for the kind of influence that abstract Forms exhert on concrete things.
    – Avi C
    Aug 29, 2022 at 4:21
  • Consider the influence of an author in world w upon a fictional world f which the author creates. From the perspective of world w, we might say the author's creative activities cause things to be the way they are in f. Although many authors also say that they write some of what they write because their characters tell them what happens next. Even setting that aside, from the perspective inside the world f, the author's influence cannot be causal. The author is not a casual agent within the fabric of f. Inside f, the author's creative activity emmanates features of f.
    – Avi C
    Aug 29, 2022 at 4:29
  • The question Platonism allows us to ask is whether the actual world in which we live is influenced by realities that are ontologically in a higher frame. If so we should expect non-causal influences (emanation) from these realities. This does not require a violation of causation in our world any more than an author's influence on a story requires causation to be violated within the story world.
    – Avi C
    Aug 29, 2022 at 4:38

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