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I've been staring at these definitions for a while now

  1. Jul 12, 2012 #1
    what is the nature of the relationship, if any, between the two?

    if parsimony is simplicity in explanation and reductionism is simplicity of mechanism, then is reductionism externally projected parsimony?
  2. jcsd
  3. Jul 12, 2012 #2
    How about parsimony is a method which allows one to practice reductionism when studying phenomena?

    I get the feeling that this is an Occam's razor kind of thing. The best explanation is most often the simplest explanation? Maybe.

    And if this were a discussion in a science textbook they would probably then want to discuss emergent properties next. Where the behavior of a complex phenomena cannot be described by looking at the simple rules that make up the components of the complex phenomena. This can be stated in a better way.
  4. Jul 12, 2012 #3
    No1: is like Fermat's Law, or Hamilton's principle... which tells you that from all the possible trajectories, the only physical one is that which minimizes your Action.

    No2: it's like theoritical models. Where you have a terribly complex phenomenon (like Lorentz's watermill ) which by making several assumptions you can type out its dynamics in simple formulas (Lorentz's watermill is written in 3 first class derivative equations).
    Or another example for No2 is statistical mechanics...
    Last edited by a moderator: Sep 25, 2014
  5. Jul 12, 2012 #4

    If the poster was staring at the initial definitions from an English dictionary... Yikes. But if he posted on a physics site maybe so.
    Last edited by a moderator: Sep 25, 2014
  6. Jul 12, 2012 #5
    what do you mean?
  7. Jul 12, 2012 #6
    Reductionism does not imply "simplicity of mechanism". It is just the assumption that the complete behavior of the system can be understood (at least in principle) if you know everything about it parts. The mechanism can be extremely complicated.
  8. Jul 12, 2012 #7
    That you may have smacked a line drive explanation right over his/her head if the OP was staring at the original definitions from an English dictionary.

    But then again, maybe not, if the OP posted this on a physics site maybe they were looking for a much more formal explaination.
  9. Jul 12, 2012 #8
    hold on, it's really easy to confuse these definitions of "simple". i'll try and reiterate my concern. let's see if i've made a mistake somewhere:

    true, reductionism isn't primarily about parsimony in terms of information content, (occam's razor) but focuses on explaining complex behaviors using a smaller number of elements. nevertheless, it seems to me that reductionism still ties into the principle of parsimony and makes physical explanations ultimately simpler by cutting down on the number of predictably orderly interactions as far as we can reasonably get away with it.

    however, before reductionism can be construed as an attempt at the introduction of theoretical minimalism into physics, (or as pgardn suggests, the other way around) is it ever possible for a theory with the minimal number of elementary components to be less parsimonious in terms of information content than another? (i mean, disqualifying at the outset theories that artificially inflate its entities, obviously, else there would be no point to this comparison)

    (edit: i suspect that if you accept a mechanical ontology, then the answer would be no, because physical components would be synonymous with the entities we're seeking to minimize. unfortunately, the question still remains, what should i make of this in light of the revelations in my previous thread? (edit edit: kolmogorov, of course, defies any such mechanistically oriented definition of "information".))
    Last edited: Jul 12, 2012
  10. Jul 12, 2012 #9
    whoa, ho down there big fella...

    You can expand at this level and you were staring at a dictionary?

    Put the book down and walk away.
  11. Jul 12, 2012 #10
    The relationship between the two is context. Words only have demonstrable meaning according to their function in specific contexts. Hence, all the diverging attempts here to explain the difference between to simple words that can be found in any dictionary.
  12. Jul 12, 2012 #11


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    I want to point out that this thread was dumped here from another forum, it doesn't meet the crtieria for this forum either.
  13. Jul 25, 2012 #12


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    Let me throw in my opinion here.

    The principle of parsimony is better stated to be the concept associated with science, where, when two competing theories are equally powerful (explain the same phenomenon equally well), the one with the lower quantity of individual assumptions should be the one favored. It's called having a more potent theory.

    Reductionism is better stated to be a worldview associated with science that says that any theory of lower scale (for example: chemistry) can be mapped onto a theory of higher scale (for example: neurology) and vice versa. Typically, the higher scale theory is one which explains the recursive processes that emerge from the lower scale (their emergence is the opening up of a higher scale).
  14. Jul 27, 2012 #13

    Looks like a perfectly legit thread to me. It's hard to prove anything in philosophy, much less when one idea is legit or not legit.
  15. Jul 27, 2012 #14
    Parsimony: If you can explain A using entities X Y Z, then there is no need to posit entity B.

    Example: Physicalism runs into a real problem with this in terms of consciousness. Physicalism as defined by Nagel is we are our bodies. If you can explain all human behavior with reference to atoms, molecules, organic compounds, neurons, etc, then there is no need to posit an additional entity, consciousness. Most physicalists however, except for eliminativists or fictionalists (also known as instrumentalists) do believe in consciousness yet they run into contradictions when they say that everything is atoms and the forces that act on them.

    Also I want to point out that someone mentioned that parsimony is the principle that the scientific theory which posits the least amount of assumptions is preferred. That's correct. In my above definition, X Y Z are assumptions, whereas A is not an assumption but is proven to exist due to X Y Z but XYZ are not proven.

    Reductionism: A is nothing other than B C and D, A reduces to B C and D.

    Example: Water reduces to H2O. Lightning reduces to an imbalance of charge between the clouds and the ground and the electrons releasing photons when they descend in their energy orbits. Protons reduce to three quarks.
  16. Jul 27, 2012 #15


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    "then there is no need to posit an additional entity, consciousness."
    No, you don't need to posit that as an "additional entity".
    Rather, the evident existence of consciousness needs to be explained, for example as a physical phenomenon, or assemblage of such.
  17. Jul 27, 2012 #16
    I am not a physicalist. From what I've seen they never spell out what a physical phenomenon is. They just call things physical. Some physicalists are not at all that different from dualists, they just believe the same things but call themselves physicalists. It's a very common thing in philosophy. Take the universalists/nominalist debate. A lot of nominalists were universalists they just called abstract objects different names.
  18. Jul 27, 2012 #17
    I like the above.

    I dont think these words were meant to go any deeper than this. There is no formal math associated with these terms. Its folly to try to read too deeply into an English dictionary. The language evolves, context, etc... One just cant get so formal. You could tear up half the book. Humans do not always have good logic and formal math behind words and even ideas. I think OP needs to go back and look at the purpose of a dictionary, as well as how it is used by most people.

    Now if we are no longer using the dictionary as the basis for these words and meanings. Carry on. You can bend it to your will.
  19. Jul 27, 2012 #18


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    I'm referring to meeting the guidelines for starting a thread, but I figured it was close enough to allow it.
  20. Aug 2, 2012 #19
    I'll give my view on this. Keep in mind, there usually no set definitions, much of philosophical reading is highly contextual.

    Parsimony - The creed to simplicity. This is not always justified, but the basis is that the idea can be subjected to probabilistic analysis which generally favours fewer terms due to the multiplicative nature of probabilities.

    Reductionism - Can be best understood by contrast to reification: the making of the nebulous to be concrete. In reverse, reductionism is used often to imply the making of the concrete into postulates.

    From this, you should find that the impetus is different. In parsimony, a purely probabilistic consideration is being made. Reductionism seeks to find the basis of a concept. As such, parsimony can be applied to a reductionist argument and reductionism can eliminate non-essential postulates for parsimonious reasons.

    At least this is the lie I've been living with for some time now.
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