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Is everyting observable?

  1. Sep 11, 2007 #1
    Science works on the simple principle of observation, experimentation and conclusion. But, is everything observable and mesurable in this universe. What about those things that might be beyond our senses.(Say if we lack a sixth sense.) The question came to my mind when I asked myself a question "If humans were blind?" Will we have ever been able to know that there is something like light?

    The world is not merely measurable. Most of the attributes of this world are subjective and non measurerable. Can science measure beauty?
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  3. Sep 11, 2007 #2


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    If there exists something that is not observable in any way, how could you even know it exists? Saying "not observable" means it cannot affect you in any way.

    Certainly if all humans were blind, we would still be able to observe, say, the warmth of sunlight on the skin, electro-magnetic properties, with the correct tools, etc.

    What do you mean by "attributes of this world"? Surely there exist things that cannot be quantified- such as value judgements. Science does not pretend to say anything about them.
  4. Sep 11, 2007 #3
    Direct observation using our limited human senses is not essential in science. We can deduce the presence of a magnetic field without observing it through its effect on other observable items. If we were all blind, we could likewise deduce the presence of something we might call "light" by noting how plants tend to position themselves, among other clues. In fact, everything that matters necessarily has some effect on us, either directly or indirectly through other entities. We normally call these things "real". They are relevant, they matter. Anything else that cannot possibly have any effect on us, either directly or indirectly, is truly not relevant to anything or anyone and can be ignored as not being real without fear of consequence. And science of course is not concerned with what does not matter.
  5. Sep 11, 2007 #4


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    Hi prtcool,
    Qualia are not measurable in the conventional sense as far anyone can tell. They are subjectively observable, meaning we can see the color red, we can hear a tone, we can feel if something is hot, we can experience qualia directly, and we can measure the corresponding physical parameter in some way. However, we can't measure experience itself as far as we know.

    What if people had an organ that could experience gravity directly instead of by the force it produces. We might for example, be circling the Earth in a satellite, and direct this gravity organ out the window and experience gravity directly. We might then perceive a very strong, almost constant gravity which was circular in the exact same shape as Earth, but we would experience a gradual decline in gravity as we directed this gravity detecting organ away from the Earth. We might percieve gravity fading away the farther we directed this organ away from the planet. Similarly, we might experience a much stronger gravity when we directed this organ at the sun.

    I’m not suggesting that such an organ is possible, but it’s interesting to consider that we similarly have no way of knowing how various qualia may differ when experienced by other living organisms. Sharks for example, have “electroreception”. What would it be like to experience such an organ if we had one? Regardless of what it might feel like, there is nothing we can do to measure this experience. Qualia are simply not measurable in the conventional sense.
  6. Sep 11, 2007 #5
    is everything observable?

    perhaps a better question is 'do we observe everything that is observable?'
    the answer depends more on psychology than on physics.
  7. Sep 12, 2007 #6
    Hi to all,

    Thanks for your replies. People said that nonobservable things are not real. But what makes us believe that non observables can't have an impact on us. Today science measures on parameters like energy and forces. What if there are energyless objects in this universe. Our current method of measurement will never help us detect such objects. What if these energyless objects have an emotionless impact on us, again a non measurable quantity. I am basically refering to things like ghosts and spirits! :smile:

    The more precise question is: Do non measurable aspects like beauty and emotions, have an impact on the uniiverse.
  8. Nov 14, 2007 #7
    There are unobservables out there. An example is an "electron". But science tells us an awful lot about these unobservables, or at least claims to.

    Why should we believe these claims?

    Well think of it this way: inference from the observed to the unobserved and inference from the observable to the unobservable are both forms of inductive reasoning. According to Hume, we can't justify any inductive reasoning. But we all believe conclusions stretching from the observed to the unobserved, e.g. from the past to the future (the Sun will rise tomorrow).

    Do we have any principled reason for disbelieving conclusions about unobservables more than we disbelieve conclusions about the unobserved?

    I don't think we do. Believing either takes a leap of faith - or a leap of truth-tropic induction, depending on your views re. Hume.
  9. Nov 14, 2007 #8
    Air and gravity have an impact on us. So I'm not sure what you're referring to?

    Energyless objects? There's no such thing.

    Oh, ok. Now I know what you're referring to, except that ghosts and spirits don't exist.

    No. Beauty and emotions are human constructs.
  10. Nov 24, 2007 #9
    Yes, they are in fact a part of the universe, and specifically affects bodily functions like the nerves and our brains.
  11. Nov 28, 2007 #10
    Do beauty and emotion impact the universe?
    They definitely impact the universe in the sense that we as humans have physical reactions to them.

    If I'm sad, then the functions of my body that create tears go into motion. If I'm embarrassed, the functions of my body that cause me to blush go into motion. There are physical reactions from our conceptions of emotion and beauty which impact the universe.

    The real question is if emotions tangibly exist. There are "non-observed entities" that I would say exist. An easy example could be something like a Bloodhound's sense of smell. Humans do not have the sense of smell that bloodhound's have, but we still infer that bloodhounds are perceiving something even in light of the fact that we do not perceive the smell. We understand that a stronger perceptual system will be able to perceive things which a weaker perceptual system could not. And where do we draw the limit to this. Do we say that the best perceptual ability is the end-all decider of what exists in the universe? I'm not so sure about that, for we would have to ignore the best perceptual system's inferences since he/she/it could not directly perceive those inferences. To say that something is unobservable seems to suggest that it is impossible to observe. If something has tangible existence, then it exists regardless if we observe it or not. We know that our abilities are limited.

    As for emotions, they seem to be resultant mental states from the processes in our brains. Are they tangible? depends what you mean. Can you hold emotion and beauty in your hand? No. But I would say that the physical processes which give rise to our conceptions of "beauty" and emotions" are tangible and the resultant feelings that we label as beauty and emotions are perceived. This gets into a lot of philosophy of mind stuff. If someone is a physicalist and believes that the universe is made completely of particles and unconscious matter, then there is a problem with terms like "emotion", "beauty", "consciousness" since these things cannot be measured and understood as being made of particles and elementary matter. My opinion is that the feelings which we characterize as "emotion" have an existence. They rise out of the physics of the mind.
  12. Dec 9, 2007 #11
    I would say that it cannot affect you in any way that you are conscious of. A bit of a difference there, but an important one. As our technology increases so does our ability to observe the universe. We are constantly observing new phenomena that at one point we didn't even know affected us. I would say that it is very probable that there are things that exist that are not currently observable to us.

    As each question leads to an answer, more questions are asked. With the data provided by answering the last question we may be able to answer one of the new questions. We can't logically answer a question that nobody has asked yet, but we should hope that someone will eventually ask a new question.
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