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Measurement & Existence

  1. Aug 20, 2006 #1
    Can we agree that "all existents can be measured" ? By existent we mean "an entity (thing) of a specific nature made of specific attributes". By measurement we mean "the identification of a relationship between an attribute of an entity and a standard that serves as a unit". Thus can we agree also that "the immeasurable does not exist" ?
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  3. Aug 21, 2006 #2
    Can something be made of attributes?

    I suppose that's the real question. Is my keyboard partly made of width and height? Are people made of heat and speed?

    But, then, isn't heat made of speed?

    This helps preserve the notion that attributes exist, because, if an attribute is not an entity of a specific nature made of specific attributes, then it doesn't exist. I suppose you'd have to make an exception for those attributes that are not made of other attributes.

    You know... if they exist. :smile:
  4. Aug 21, 2006 #3


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    Hot macro systems are made of moving microsystems. Heat is a name. I would say speed is a name too, its role in the kinematics of relativity just a place holder for a group symmetry in an "effective theory". As the man said, we are made out of spacetime, and gee, many don't accept that as a thing either. Maybe ontology should be dropped for a few years till the scientific picture becomes clearer?
  5. Aug 21, 2006 #4
    Yes, every "thing" is made of attributes, and the total of these attributes "are" the entity. There are no attributes without first an entity--width for example does not exist in reality as a Platonic form--it exists as an attribute of entities, in the case of your keyboard, as an attribute of specific parts that form it. An attribute is never an entity, attributes are invisible.
  6. Aug 22, 2006 #5
    Ontology can still provide speculation on sub-microsystems. Wolfram's cellular automata is really a kind of advance in ontology. I wonder if Cartesian ontology played a role in the discovery of heat as moving microsystems?
    It sounds like there is a priori/posteriori conflict here. Entities are made of attributes, but attributes cannot be originally applied to entities, because entities must exist prior to them.

    How do you explain mathematical attributes that were understood before they were applied to entities? We knew of complex numbers before knowing that electromagnetism had complex attributes. We know of hypercomplex numbers, so is it guaranteed that entities with octonion and sedonion attributes exist?
  7. Aug 24, 2006 #6
    But, a "complex number" is not an attribute, it is an entity--see this link:http://en.wikipedia.org/wiki/Number. Each complex number as an entity has the attributes of "negative" and "square root". So, for your argument to hold you would need to give examples of a priori existence of "negative" without reference to an entity--same for "square root". As to your comment about priori/posteriori problem, I think this is a false dichotomy. IMO it is better to think of the two (e.g. entity+attributes) as a dialectic--the entity is the integrated total of all of its attributes. While the attributes are established through mental abstraction, the entity is real.
  8. Sep 1, 2006 #7
    Measurements tells us about reality but is not reality itself. I think science is limited in this area such as the problem of a singularity.
  9. Sep 5, 2006 #8
    A measurement, by definition, implies a measured and a measurer. This raises the question of "measurement by whom?" - since any measurement entails a perspective (is subjective). In science we make the approximation that most measurements can be assumed to be objective (except in QM where objectivity is almost impossible to achieve), but in principle there is always an element of subjectivity (or perspective) in every measurement.

    But since measurements are subjective, it may be the case that not all things can be measured from all perspectives - there may be some properties which require a particular perspective in order to be measured. On this view, the subjectivity (and inaccessibility to 3rd person measurement) of conscious experience is easily understood. Just because an external observer cannot measure the precise subjective properties that you associate with your conscious perception of the colour red does not mean that your conscious perception does not exist - it means only that your precise conscious perception is subjective (known only to you) and is inaccessible from that 3rd person perspective.

    Best Regards
  10. Sep 5, 2006 #9
    Yes, thank you, but--the OP statement holds (e.g.,all existents can be measured) since the conscious perception of colour red is measured by someone, e.g., the person having the perception, and that is all the OP question asks.
  11. Sep 5, 2006 #10
    Wel I would not agree with that.
    Just because we cannot measure something does not imply it does not exist.
    So, would you be of the opinion that say 100 years ago neutrinos did not exist because obviously they could not be measured? And even now we can hardly measure them.
  12. Sep 5, 2006 #11
    I do not say that existence requires measurement for existence to exist, my OP has to do with question of whether or not any existent can be measured. Thinking on this I reach the conclusion that "all existents can be measured". To falsify this statement I would need example of "some existents cannot be measured" (I cannot think of such example, that is why I ask). Of course neutrinos 100 years ago had potential to be measured, as we do today:--see: http://council-strategygroup.web.ce...ons/Long.pdf#search="measurement of neutrino"
  13. Sep 5, 2006 #12
    Clearly you state that:

    1. Everything that exists can be measured.
    2. Something the cannot be measured does not exist.

    Again, I disagree with that. There could very well be things that are unmeasurable for us but still exist and even influence other things.

    Let me pick an example:
    It is not impossible that what determines a particular quantum output is some internal deterministic mechanism that is hidden from us. Would you in such a case claim that by your logic it thus does not exist?
    Last edited: Sep 5, 2006
  14. Sep 5, 2006 #13
    I agree with MeJennifer - there may be some things which exist which we (presently) have no way of measuring (detecting). (But then I would also say that if it is impossible in principle to detect something then, FAPP, that something does not exist - it is meaningful to talk of existence of entities only in the case where such entities are at least in principle possible to be measured/detected). (I suspect we will likely also get into a discussion on what "measurement" or "detection" really means)

    We must also understand that "X can be measured" does not mean "anyone and everyone can measure X" - which is where many people (eg Chalmers etc and his followers) seem to have a problem with understanding conscious existence.

    Best Regards
    Last edited: Sep 5, 2006
  15. Sep 6, 2006 #14


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    This puts our philosophical knowledge basis into a contingent state. That's sure fine with me, emotional nominalist that I am, but can you guys with your devotion to a priori systems deal with it?
  16. Sep 8, 2006 #15
    What about the heisenberg uncertainty principle? In quantum physics you don't deal with exact measurements, you deal with statistical probability
  17. Sep 8, 2006 #16
    To say that we cannot have infallible knowledge of the world is not the same as saying that the world is in any way ontically indeterminate/unreal/uncertain. Fundamental limitations to our epistemology do not necessarily reflect any kind of ontic contingency/uncertainty/imprecision/unreality etc.

    The same applies to the HUP. The HUP is an in-principle limit to our epistemology, it does not necessarily entail ontic indeterminism.

    Best Regards
    Last edited: Sep 8, 2006
  18. Oct 18, 2006 #17


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    Doesn't the OP imply the following?
    1. nothing really exists below the Planck scale,
    2. nothing exists outside of our "event cone." (Mesurent entities who have nonidentical event cones necessarily disagree about what truly exists and what doesn't. I guess that's okay if they don't ever meet.)
    Last edited: Oct 18, 2006
  19. Oct 19, 2006 #18
    I would disagree with the thread starter. Our knowledge is based on the human experience and perception (as said previously, much of which is subjective). So to say that "if it cannot be measured, it doesn't exist" assumes that we are capable of percieving all things in their "real" form and we are incapable of being decieved by the senses.

    When I say "real" I mean that it's possible we are percieving things not as they are but simply as our minds and bodily functions make them out to be. Descartes anyone?
  20. Apr 17, 2007 #19
    It is interesting that we function despite our lack of understanding of all that is reality. Apparently being ignorant of all that it is, is somewhat blissful, that is untill we ask a meaniful question. Our model of Reality while not being complete is sufficient for the time being. At this moment in time, we are close to understanding enough to allow us more freedom in the universe. Our existance of course is threatened by our lack of social and humanitarian skills. But then that is subjective Reality and some might say the same of objective Reality, it is subjective as well.
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