“Emergence” is on of those terms like “information” that is always getting overloaded and confused between casual meanings and technical/applied definitions.
I think the definition you have cited (source?) is not too far off, but is off by enough to get the wrong conclusion when applying it here. Water, for example, has “wetness”, a feature we consider an emergent property, manifest in water-as-liquid where neither hydrogen or oxygen exhibit that feature.
As it turns out, and has been discussed here previously, “wetness” isn’t magic, and while we are just nominally informed now on the mechanics that arise from the physics of combining a hydrogen atom with two oxygen, we can indeed predict and anticipate the feature we call ‘wetness’ in water.
There’s a response to this, then, that says that “wetness” is and was not an emergent property after all. There’s merit in that, but only as a matter of finality, and “in principle” epistemics. Emergence is
not, contra the claims of many (and some here), analogous to ‘magic’, or some kind of animist voodoo science for some reason has taken a shine to. Rather, as in the example of ‘wetness’, the mechanics are assumed to be as discoverable
in principle as any other natural mechanism or process.
We use “emergent”, as a reflection of the feature’s epistemic status. Particularly, we are interested in using the term when
the higher order phenomenon is more readily predictable and modeled on its own terms than by reduction and “bottom up predictions”. That is, we can predict and model thermodynamics on its own terms more readily than we can derive it from the underlying statistical mechanics (that is, the physical dynamics we refer to by ‘statistical mechanics’).
This means that emergent properties are predictable, or more precisely, derivable by lower level physics in principle, but in practice, we come to understand the higher-level dynamics far earlier and more readily than through derivation. We assimilate “wetness”, then, into our knowledge base, into our empirical repository, far earlier than we come to know the physics of hydrogen and oxygen bonds. This we call “emergence”.
We could not, in practice, have begun with our knowledge of hydrogen and oxygen and predicted “wetness”. But “wetness” isn’t magic, and the mechanics required for emergent property explanations lagged far behind the knowledge and experience of hydrogen/oxygen
and wetness as first order phenomena.
That’s an admitted subtle, but profound distinction, and one that the brief blurb found by Yahoo! for you missed.
Tim Crane’s book
Physicalism and its Discontents is a good resource to consult here – this page link will jump you right to a discussion on just this point:
books.google.com/books?id=oG7J1fQMwzEC&pg=PA216&lpg=PA216&source=bl&ots=X6FyDCeCj3&sig=EFMdzhF868-fDeWj5eyhf_VuTAs&hl=en&ei=m2YxS7zTN42sngf4-6jyCA&sa=X&oi=book_result&ct=result&resnum=2&ved=0CBEQ6AEwATgK#v=onepage&q=&f=false
Just a paragraph here, for the large majority that can’t be bothered to click through:
Read beyond that, it’s a quality treatment of the subject.
-TS
), the quote expresses my understanding (and obviously not just mine) of what an emergent property is generally supposed to be. Anyway, how is it “off by enough” such that we would “get the wrong conclusion * when applying it here [where, exactly?].” RD had attempted to make an emergentism analogy (for the emergent property of consciousness, etc.) based on the behaviour of refined U-235; your contribution here is interesting, but its apparent pretentions to say something that is relevant to the foregoing discussion seem exaggerated.*
