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Comment by ClayFerguson | Hacker News Reader

"Emergence": Most everything in science (from Chemistry to Consciousness) is an emergent phenomenon and most people are plain ignorant of the concept and meaning of that word, although I did see it appear a lot in 2016, in scientific articles. The only thing (or things) in science that are not emergent are the laws of Quantum Mechanics and Relativity (as a simplification), and there are more and more physicists that believe even both of those "rule sets" probably are emergent from some more fundamental and simpler set of "rules", that give rise to both QM, Gravity, Spacetime.

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My problem with emergence is that it makes you think in one conceptual direction, and not the other.

To explain, emergence as stated in the parent is a name for how a bunch of molecules could interact to make something you might call a football. This is a phenomenon at the "higher" everyday physical level emerging from the phenomena of the "lower" chemical level.

What I think this story misses is the importance of the "even higher" phenomena which resulted in a football being created, those of the human cultural level which caused the football to be manufactured and, for example, placed on some grass, or a desk, to be studied.

This isn't a purely sociological or philosophical point either, when you're looking at brain macro-activity for example, it's only partially explicable by referencing the micro-activity of, say, individual neurons, to get a better understanding you need to refer to activity outside of the brain that caused certain individual neurons to be acting like that. These higher level phenomena can be simple things like the movement in the neck that caused a change in stimulation, and also more wooly concepts like cultures which provide certain aesthetics or behaviours.

Emergence is important, but I feel its too often considered as a standalone phenomenon, rather than as one side of an irreducible causal cycle.

Emergence is a broad term for when things with definable, reproducable, novel, and predictable behaviors, which can be studied, quantified, and have math rules written about them, arise spontaneously from the lower rule-sets they are built on. It's like when you can identify a separate and distinct set of behaviors in the causality chain, but yes the word 'causality' encompasses 'emergence' in a very vague way, and so vague that it's indistinguishable from 'time' itself.

Relevant Less Wrong post:

http://lesswrong.com/lw/iv/the_futility_of_emergence/

The best way to explain emergence, is with an example, imo. The classic example is to look at Conways' Game of Life, and ask yourself what God must have 'designed' the 'lifeforms' that appear in it. Where is their behaviors encoded into reality to make them become real (i.e. happen). The answer is that they are not specifically designed but instead 'emerge'. Not that your snarky 4 word joke of a post deserved a response though. This is for others, not you.

Emergence as a concept only serves to eliminate the need for a designer. It doesn't actually explain anything to someone who already accepts the possibility of complexity without design. But that doesn't mean it's a useless concept, just that it is sometimes misused (if the LW post's premise is true).

Right, Emergence is a general term like Entropy, and I chose that on purpose because Emergence is more like the negative of or inverse of Entropy. Emergence is when you get order, complexity, and non-randomness out of pure randomness plus time plus rules.

While I agree with Eliezer that "emergence did it" is no more of an explanation than "god did it", I'm not sure that this is the meaning people are trying to convey when they say e.g. "intelligence is an emergent phenomenon". What the statement means to me is that intelligence is a computationally dense phenomenon. This doesn't rule out the possibility of understanding it from a lower level, but it does rule out _simplifying_ it to the point where it can be understood without performing large computations.

In my mind, the concepts of irreducible complexity and emergence are inherently linked through the concept of abstraction. An emergent phenomenon is a computationally dense phenomenon for which much of the computation can be abstracted away, at the cost of giving up a low-level understanding. In a sense, emergence is the antithesis of irreducible complexity. In another sense, emergence is a sparse chain of islands in a sea of irreducible complexity.

> The only thing (or things) in science that are not emergent are the laws of Quantum Mechanics and Relativity (as a simplification)

By "relativity" I'm assuming you're referring to SR or GR here. I always thought of relativity as an emergent phenomenon due to the large scales we are working with. What makes you say it is not?

There are currently no good theories about why SR and GR hold true. They appear to be as fundamental as QM, but are totally independent of QM. QM always obeys SR/GR in terms of how spacetime behaves, and how mass affects things, etc, but there is no theory that says Relativity is true 'because of' QM (or emerging from QM), although that is a goal that is being searched for. It would be nice if either QM caused GR or vice versa, but no one has a clue how it could be true yet.

> QM always obeys SR/GR in terms of how spacetime behaves, and how mass affects things, etc.

We still haven't experimentally verified how gravity works on atomic scales, though, have we? I consider it completely plausible that it works differently than GR postulates, because to me (non-physicist here) GR seems to be a "large numbers" phenomenon and assumes space possesses certain properties that it may very well not possess on small scales (e.g. any kind of smoothness or even continuity).

We have verified (experimentally) that individual particles, whose quantum properties can be individually measured, do obey the rules of SR/GR. That is, space is curved for them in the presence of mass, and time slows down based on velocity, etc. Everything about QM that involves spacetime, has to be considered using the Relativity definitions of spacetime. Non-relativistic classical calculations will give the wrong answers always and relativistic is always right. Gravity only 'appears' to be a 'large numbers' problem because it's effect is so weak compared to EMF, as far as is proven. But my opinion is it's 50/50 chance that in the end SR/GR actually is emergent from something more fundamental rather than "that's just how it is."

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