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Experiences are a priori

  1. Apr 1, 2004 #1
    A posteriori does not exist as memory is a thought process. You cannot communicate or even remember anything without thinking first and so therefore the only method of knowledge and understanding must be a priori.

    You cannot claim that a car is green or you have just gone to the toilet as you have had to process the concept of a red car and going to the toilet before you can realise that you have experienced these. Of course you can claim that a posteriori knowledge and a priori knowledge are merely distinctions between inference and fact, but by definition posteriori can only exist if we happen to be omnipotent and do not require physical processes in order to perceive and remember.

    You can claim that we are sentient and that is supernatural enough, however if you were to perform experiments on your brain, you would seee that your sentient self is affected. This implies that despite the fact you are sentient, you are still under the dictate of physical processes, a posteriori does not exist and a priori is the process in which all knowledge is attained.


    You are currently perceiving a red flower. If you were to sever your optic nerves you would stop perceiving a red flower, this is because a process was involved that involved processing the image and realising that it is a red flower.

    The examples can get even simpler.

    You claim that the activation of a nerve next to a part of the brainthat will make you perceive something is a posteriori as the processes involved are so simple that they cannot possible be a priori. You infer that you are perceiving something, the detection of this sensation is a priori.

    Of course you can also claim that everything is a posteriori as the 'circuits' that define our brains are themselves 'sensing' each other directly, though again, by definition no matter how simple the mathematics involved in perception and thought all knowledge must be a priori.
  2. jcsd
  3. Apr 1, 2004 #2
    ...Also known as the Rubicon of Solipsism. How one deals with that bridge defines how one deals with everything. Cattell had some words to say about this, but I don't think his answer was internally consistent.

    • Accordingly, let us turn to epistemology, the branch of our
      philosophy which deals with the nature of our knowing (and the
      related ontology, which deals with the nature of being). Here the
      first Rubicon to be crossed is that of _Solipsism_, which developed
      from Berkeley. If waking experience and dream cannot be
      distinguished, the whole universe could be a dream by one man (an
      extremely ingenious man). There is no logical way of crossing the
      obstacle of Solipsism; and it must surely be set aside, ultimately,
      by probability, and the privileged position reasoning has always
      given to the _simplest_ explanation. After absolute Solipsism, we
      meet the objection which Hume developed that we can never "know" the
      external world directly: that our sensations are different from what
      causes them. This does not bother the scientist, who is happy to
      manipulate the external world by a model of well-fitting referents or
      symbols. Our experinces of, say, red and green, are different from
      the vibrations which cause them; but from indirect evidence we know
      there is a constancy of reference. What may temporarily worry the
      scientist -- or, at least, slow him up -- is that the range of our
      senses obviously does not correspond to the range of possible
      incoming information. The dog has no color perceptions
      differentiating the red and green wave lengths; and until a
      generation ago, we had no perception of radio waves. But in time
      there is no reason why those sources of information should not be
      translated into our sensory range. Thirdly, we have to consider
      possible limitations in our symbol system for representing what we
      meet. If language were our only system (and, unfortunately for us, at
      the hands of those who demand only "freedom of speech," it _is_ often
      the only syntax and basis of logic), we should be in trouble. But
      science has developed many flexible symbol and syntax systems,
      largely as new branches of mathematics.
  4. Apr 2, 2004 #3

    Good points, but I don't think Phoenix was arguing for solipsism. I thought he was just agreeing with Aristotle et al that all knowledge begins in experience. This can be true even if solipsism is false.

    However it does follow from this that true knowledge must come from direct experience and not from systems of proof, so idealism and solopsism can never be disproved and in some form or other will always be possibly true.
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