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Consciousness

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Title: Consciousness


1
Consciousness
2
Inspiration and Invention
3
  • Penrose, Emperors New Mind, page 418
  • Poincarés experience
  • I left Caen, where I was living, to go on a
    geologic excursion under the auspices of the
    School of Mines. The incidents of the travel
    made me forget my mathematical work. Having
    reached Coutances, we entered an omnibus to go to
    some place or other. At the moment when I put my
    foot on the step, the idea came to me, without
    anything in my former thoughts seeming to have
    paved the way for it, that the transformations I
    had used to define the Fuchsian functions were
    identical with those of non-Euclidean geometry.
    I did not verify the idea I should not have had
    time, as upon taking my seat in the omnibus, I
    went on with a conversation already commenced,
    but I felt a perfect certainty. On my return to
    Caen, for convenience sake, I verified the result
    at my leisure.

4
  • What is striking about this example (and numerous
    others cited by Hadamard) is that this
    complicated and profound idea apparently came to
    Poincaré in a flash, while his conscious thoughts
    seemed to be quite elsewhere, and that they were
    accompanied by this feeling of certainty that
    they were correct as indeed, later calculation
    proved them to be. It should be made clear that
    the idea itself would not be something at all
    easy to explain in words. I imagine that it
    would have taken him something like an hour-long
    seminar, given to experts, to get the idea
    properly across. Clearly it could enter
    Poincarés consciousness, fully formed, only
    because of the many long previous hours of
    deliberate conscious activity, familiarizing him
    with many different aspects of the problem at
    hand. Yet, in a sense, the idea that Poincaré
    had while boarding the bus was a single idea,
    able to be fully comprehended in one moment!
    Even more remarkable was Poincarés conviction of
    the truth of the idea, so that subsequent
    detailed verification of it seemed almost
    superfluous.

5
  • Penrose page 423, speaking of Mozart
  • When I feel well and in a good humor, or when I
    am taking a drive or walking after a good meal,
    or in the night when I cannot sleep, thoughts
    crowd into my mind as easily as you could wish.
    Whence and how do they come? I do not know and I
    have nothing to do with it. Those which please
    me I keep in my head and hum them at least
    others have told me that I do so. Once I have my
    theme, another melody comes, linking itself with
    the first one, in accordance with the needs of
    the composition as a whole the counterpoint,
    the part of each instrument and all the melodic
    fragments at last produce the complete work.
    Then my soul is on fire with inspiration. The
    work grows I keep expanding it, conceiving it
    more and more clearly until I have the entire
    composition finished in my head though it may be
    long. Then my mind seizes it as a glance of my
    eye a beautiful picture or a handsome youth. It
    does not come to me successively, with various
    parts worked out in detail, as they will later
    on, but in its entirety that my imagination lets
    me hear it.

6
  • Penrose It seems to me that this accords with a
    putting-up/shooting-down scheme of things. The
    putting-up seems to be unconscious (I have
    nothing to do with it) though, no doubt, highly
    selective, while the shooting-down is the
    conscious arbiter of taste (those which please
    me I keep ). The globality of inspirational
    thought is particularly remarkable in Mozarts
    quotation (it does not come to me successively
    but in its entirety) and also in Poincarés (I
    did not verify the idea I should not have had
    time).

7
Non-verbality of thought
  • Letter from Einstein The words or the language,
    as they are written or spoken, do not seem to
    play any role in my mechanism of thought. The
    psychical entities which seem to serve as
    elements of thought are certain signs and more or
    less clear images which can be voluntarily
    reproduced and combined. The above mentioned
    elements are, in my case, of visual and some
    muscular type. Conventional words or other signs
    have to be sought for laboriously only in a
    second stage, when the mentioned associative play
    is sufficiently established and can be reproduced
    at will.

8
  • Quoting Francis Galton, the geneticist
  • It is a serious drawback to me in writing, and
    still more in explaining myself, that I do not
    think as easily in words as otherwise. It often
    happens that after being hard at work, and having
    arrived at results that are perfectly clear and
    satisfactory to myself, when I try to express
    them in language I feel that I must begin by
    putting myself upon quite another intellectual
    plane. I have to translate my thoughts into a
    language that does not run very evenly with them.
    I therefore waste a vast deal of time in seeking
    appropriate words and phrases, and am conscious,
    when required to speak on a sudden, of being
    often very obscure through mere verbal
    maladriotness, and not through want of clearness
    of perception.

9
  • Quoting Hadamard
  • I insist that words are totally absent from my
    mind when I really think and I shall completely
    align my case with Galtons in the sense that
    even after reading or hearing a question, every
    word disappears the very moment that I am
    beginning to think it over and I fully agree
    with Schopenhauer when he writes, thoughts die
    the moment they are embodied in words.

10
Inspiration in animals
  • Lorenz describes a chimpanzee in a room which
    contains a banana suspended from the ceiling just
    out of reach, and a box elsewhere in the room
  • The matter gave him no peace, and he returned to
    it again and again. Then suddenly and there is
    no other way to describe it his previously
    gloomy face lit up. His eyes now moved from
    the banana to the empty space beneath it on the
    ground, from this to the box, then back to the
    space, and from there to the banana. The next
    moment he gave a cry of joy, and somersaulted
    over to the box in sheer, high spirits.
    Completely assured of his success, he pushed the
    box below the banana. No man watching him could
    doubt the existence of a genuine Aha experience
    in anthropoid apes.

11
Consciousness and Language
  • Penrose 383-4
  • Many philosophers and psychologists seem to take
    the view that human consciousness is very much
    bound up with human language. Accordingly, it is
    only by virtue of our linguistic abilities that
    we can attain a subtlety of thinking that is the
    very hallmark of our humanity ... From this
    viewpoint, our language is taken to be the key
    ingredient of our possession of consciousness.

12
  • Now we must recall that our language centres are
    (in the vast majority of people) just on the
    left-hand sides of our brains The viewpoint
    just expressed would seem to imply that
    consciousness is something to be associated only
    with the left cerebral cortex and not with the
    right! Indeed, this appears to be the opinion of
    a number of neurophysiologists.

13
  • Penrose, page 425 It should be clear to the
    reader why I find that viewpoint totally
    unacceptable. there can be no doubt of the high
    level of consciousness required for mathematical
    thought. Whereas analytical thinking seems to be
    mainly the province of the left side of the
    brain, geometrical thinking is often argued to be
    the right sides, so it is a very reasonable
    guess that a good deal of conscious mathematical
    activity actually does take place on the right!

14
Split Brain Experiments
  • Penrose, p. 384 In relation to this, I should
    mention a remarkable collection of observations
    concerning human subjects (and animals) who have
    had their corpus callosums completely severed, so
    that the left and right hemispheres of the
    cerebral cortex are unable to communicate with
    one another.

15
  • Penrose, p. 385 What is most striking about
    these split-brain subjects is that the two sides
    seem to behave as virtually independent
    individuals, each of which may be communicated
    with separately by the experimenter although
    communication is more difficult, and on a more
    primitive level, with the right hemisphere than
    with the left, owing to the rights lack of
    verbal ability.

16
  • One is tempted to raise the issue do we have two
    separately conscious individuals both inhabiting
    the same body? This question has been the
    subject of much controversy. Donald Wilson and
    his coworkers examined a split-brain subject,
    referred to as P.S.. After the splitting
    operation, only the left hemisphere could speak
    but both hemispheres could comprehend speech
    later the right hemisphere learned to speak also!
    Evidently both hemispheres were conscious.
    Moreover, they appeared to be separately
    conscious, because they had different likes and
    desires. For example, the left hemisphere
    described that its wish was to be a draughtsman
    and the right, a racing driver!

17
  • Pages 385-386 I, myself, simply cannot believe
    the common claim that ordinary human language is
    necessary for thought or for consciousness. I
    therefore side with those who believe, generally,
    that the two halves of a split-brain subject can
    be independently conscious.
  • Presumably, before the operation each split-brain
    subject possessed only a single consciousness
    but afterwards there are two! In some way, the
    original single consciousness has bifurcated.
  • The puzzle would be further exacerbated if
    somehow the two consciousnesses could later be
    brought together again.

18
Consciousness and Time
  • Penrose pp. 439-442 A number of human subjects
    volunteered to have electrical signals recorded
    at a point on their heads, and they were asked to
    flex the index fingers of their right hands
    suddenly at various times entirely of their own
    choosing. there is a gradual build-up of
    recorded electric potential for a full second, or
    perhaps even up to a second and a half, before
    the finger is actually flexed. This seems to
    indicate that the conscious decision process
    takes over a second in order to act!

19
  • This may be contrasted with the much shorter time
    that it takes to respond to an external signal if
    the mode of response has been laid down
    beforehand. For example, instead of it being
    freely willed, the finger flexing might be in
    response to the flash of a light signal. In that
    case a reaction time of about one-fifth of a
    second is normal, which is about five times
    faster than the willed action .

20
  • In the second experiment, Benjamin Libet with
    Bertram Feinstein tested subjects who had to
    have brain surgery for some reason unconnected
    with the experiment and who consented to having
    electrodes placed at points in the brain .
    When a stimulus was applied to the skin of these
    patients, it took about half a second before they
    were consciously aware of that stimulus, despite
    the fact that the brain itself would have
    received the signal of the stimulus in only about
    a hundredth of a second, and a pre-programmed
    reflex response to such a stimulus could be
    achieved by the brain in about a tenth of a
    second. Moreover, there would be the
    subjective impression by the patients themselves
    that no delay had taken place at all in their
    becoming aware of the stimulus!

21
  • See also Science 20 February 2004 vol. 303 page
    1144, The Where and When of Intention.

22
  • Conscious perception of a stimulus can be masked
    by an event about a quarter of a second later.
  • However, one does not seem to be aware of such
    a long time-delay in ones perceptions.
    Perhaps the time of all ones perceptions is
    actually delayed by about a half a second from
    the actual time . The subject does appear to
    refer the perception of the skin touching
    backwards in time by about half a second. The
    cortical stimulation seems not to be referred
    back in this way.

23
  • The apparent implication of these two experiments
    taken together is that consciousness cannot even
    be called into play at all in response to an
    external event, if that response is to take place
    within a couple of seconds or so!
  • we appear to be driven to the conclusion that
    we act entirely as automatons when we carry out
    any action that would take less than a second or
    two in which to modify a response.

24
  • Page 443 I suggest that we may actually be
    going badly wrong when we apply the usual
    physical rules for time when we consider
    consciousness!
  • Page 445 Suppose that there is even something
    vaguely teleological about the effects of
    consciousness, so that a future impression might
    affect a past action.
  • Recall my proposal that consciousness, in
    essence, is the seeing of a necessary truth
    and that it may represent some kind of actual
    contact with Platos world of ideal mathematical
    concepts.
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