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Downward Causation

  1. Apr 11, 2005 #1


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    A definition:

    http://www.st-edmunds.cam.ac.uk/cis/murphy/lecture2.html [Broken]

    More detail:


    I wanted to post these in the 'Can Everything be Reduced to Physics' thread, but it's gone so far off-topic so many times that I'm not going to bother. Admittedly, I'm being lazy by just posting links, but I'm not sure if these two presentations are compatible with each other and I have no idea why.
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  3. Apr 11, 2005 #2
    Question: Would there still be duality without space and time!? Is it not so, in the true sense of the word, that Eternity, has nothing to do with time? Is it not what time and space cuts out. Does not an Epiphiny suggest this as well. Isn't that experience why it's so good to break past all this. The real question then therefore, is what is the nature of the radiance being experienced?! No ponogrphy, no didactics, but transparancy to the radiance. To meet something you don't know, and understand?!What do you suggest?!........................MEDIUM...........................> o:)
    Last edited: Apr 11, 2005
  4. Apr 11, 2005 #3


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    Eternity, in the contemporary conception at least, is necessarily atemporal as we know from cosmology that there was an instant at which time came into existence and eternity, by definition, cannot come into existence. Whether this is truly a necessary fact of eternity or just an artifact of poorly thought-out definitions of concepts that are far removed from familiar experience I don't know.

    What does this have to do with emergent causation?
  5. Apr 12, 2005 #4
    Hi. I found the second link to be better written than the first. The first uses a poor example: the ant jaw example involves a temporally extended feedback loop which seems understandable without reference to downward causation. It also talks about "activation" of constituent part's causal powers by higher level properties, which isn't particularly insightful.

    Anyway, my own view is that the notion of downward causation is a vague placeholder for a more complete account of the behavior of complex systems. I do think there is a real issue here: we don't have an adequate account of causation for complex macro-level phenomena, even though many assume we do. But just asserting that there exists something called downward causation (like asserting there exist "emergent" phenomena) isn't satisfying.
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  6. Apr 13, 2005 #5
    I agree that the second article is more informative and better-written, but I find both articles to be rather simplistic and misleading.

    The latter article talks of the dynamics of ice crystal growth in terms of "state-space attractors", and argues that "which attractor will be eventually reached is totally unpredictable from the point of view of the molecules. It rather depends on uncontrollable outside influences. But once the attractor is reached, it strictly governs the further movement of the molecules."

    What on earth is an "uncontrollable outside influence"? What I think the authors are (or should be) trying to say is that the deterministic causative influences of ice crystal growth are to be found in numerous (complex and often chaotic) environmental factors. To me this would seem to be an example of "downward causation" only in the sense that we can maybe make better intuitive sense of what is happening (we can maybe understand what is happening more easily) by “thinking” in terms of holistic downward causation rather than in terms of reductionist upward causation. But (to me) this is all that downward causation is – an aid to understanding what is going on. Unfortunately this can also lead to confusion and errors in understanding. It does not actually mean (in this example) that there are causative influences at the holistic level which are determining the growth of ice crystals. All of the causative influences are “upward” rather than downward, and can still be undertsood (albeit with great difficulty in complex cases) via the upward causation reductionist method.

  7. Apr 13, 2005 #6
    I agree with you here, MF. I remember reading an explanation for the uniqueness of snowflakes somewhere recently. I am not good at remembering details, so I'll give you my recollection of the gist of the explanation as best I can.

    Ice crystals form along 2 (or it may be 3; one of the details which may be wrong) different axes. When a particular gas molecule with the right amount of energy comes in contact with the growing crystal, it might align itself along one or the other of those axes. The choice is made by critical differences between temperature and humidity in that region. Certain combinations of values of temperature/humidity will favor one axis and others will favor the other axis. The particular combination at one moment will favor one axis, so gas molecules ready to attach will all align along the same axis relative to their point of attachment since the temperature/humidity will be nearly the same over the entire region of the snowflake. Thus each attachment contributes to the six-fold symmetry. But the very action of those molecules attaching immediately changes the temperature and humidity in the region of that crystal. This new combination may or may not change the preferred axis, but the effect is local only to that snowflake. So as the snowflake grows, the pattern of which axis is preferred at each successive stage of growth is determined by the local environment and the local feedback loop. The number of molecules in a snowflake is large enough that the combinatorics of the axis choices leads to the uniqueness.

    It's sort of like that.
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