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The anthropic principal

  1. Apr 16, 2005 #1
    Does the anthropic principal support the design argument and just what does it mean?
  2. jcsd
  3. Apr 16, 2005 #2


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    The anthropic principle just states that because we exist, then our universe must be a universe in which all physical constants are such that intelligent life can exist. Some physicists believe this might have predictive value in that we can guess at what certain constants will be (at least within a sometimes broad range) before we have discovered them. As such, it doesn't imply design, but many take the leap anyway to say that having a universe with physical constants that can support intelligent life shows that the universe was designed for that purpose.
  4. Apr 17, 2005 #3
    If the physical constants and laws of our world are indeed "finely tuned" to support life, there are several possible explanations as to how this could have come about.

    Design : There is just one world with one set of physical constants and laws, and it was designed that way (by whom?) such that life could exist. This implies that life is somehow "special" in the Copernican sense.

    Good Luck : There is just one world with one set of physical constants and laws, there is no external designer but these all follow from some grand Theory of Everything, and we are just incredibly lucky that life could exist. This implies again that life is somehow "special" in the Copernican sense.

    Multiple Worlds : There are many (possibly an unlimited number of) worlds, each with a different set of physical constants and laws, and only in some of these worlds are the physical constants and laws compatible with life, and life thus necessarily exists only in compatible worlds. This implies that life is NOT "special" in the Copernican sense.

    IMHO this last explanation (or a variant of it) is what most people have in mind when they talk of the Anthropic Principle - the reason we live in a world which is compatible with life is simply because we would not exist in a world incompatible with life.....

    See also
    for more discussion on this.

  5. Apr 17, 2005 #4
    When many people talk about the "anthropic principle", they are talking about just what you are mentioning here. I find it to be a philosophical pile of self-serving dog crap. It is a belief based out of emotion.
  6. Apr 17, 2005 #5
    yes, that is a very interesting logical argument.
    have to remember that one.
  7. Apr 17, 2005 #6
    I think it is a misunderstanding between these two statements . . .

    We are here because the conditions are right.

    The conditions are right because we are here.

    The first one, I think (correct me if I'm wrong) implies that the right conditions are the cause of us. The second one implies that we are the cause of the conditions being right. I dont think that the anthropic principle itself says either way.
    Last edited: Apr 18, 2005
  8. Apr 17, 2005 #7


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    Correct, and the problem is that you cannot distinguish between the two statements by scientific observation if you cannot observe other universes where the physical constants are not propitious for life.

    It may even be the case that we will never be able to 'see' outside our continuum of space-time i.e. our 'universe'. It that case both statements will continue to have equal scientific validity.

    Last edited: Apr 17, 2005
  9. Apr 18, 2005 #8
    It is a assertion that has no basis. People believe it because it makes them feel good. It makes them feel special. It makes them feel like part of a larger purpose.

    Everything is governed by necessary mathematical laws which have no concerns, no desires, and no goals. There is no room in that for design or purpose.
  10. Apr 19, 2005 #9


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    "People believe it because it makes them feel good." - and does your rejection of it make you feel good?

    Beware of personal bias here; it works both ways.

    From a scientific point of view it depends on what you can demonstrate observationally and experimentally. Here, where we confront the boundaries of science, the ability to observe fades and personal bias takes over!!

  11. Apr 19, 2005 #10
    just the opposite. The Anthropic Principle, like the Cosmological Principle, says that "humans are not special"

    Unlike many cosmological explanations, the Anthropic Principle is silent on whether there is or is not any design or purpose in our world.

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