Tuesday, January 30, 2007

Interaction Simultaneity

Chapter 4 Principle of Interaction Simultaneity

"One thing should be remarked here. Such a mathematical description is physically meaningless unless the way we construct time is made clear. All our judgments about time is one about events that occur simultaneously. "

Albert Einstein, in his first paper on special relativity (1905)

4-1 Physical time and psychological time

What is time? This is one of the most profound of all scientific or philosophical questions. We humans are mortal. Our life has been likened to be "a preparation for death". Death is an inevitable change that visits all living organisms eventually with the flow of time. The enigma of death cannot be separated from that of the flow of time.

It is one of the most fundamental challenges in the so-called mind-brain problem to clarify how the psychological flow of time arises. What is the fundamental reason why we remember only the past, and not the future? How is it that does that we are apparently able to change the events in the future to some extent with our "free will" (or, in a more scientifically tractable term, "agency") but not events in the past? How "long" in terms of physical time is the psychological present? Why is it that the psychological time seems to flow continuously from the "immediate past" to "now", and then on to the "immediate future?"

In the previous chapter, we discussed the "interaction picture" as opposed to the "statistical picture", in which elements of perception are formed as an interaction-connected cluster of neural firings. In this process, we arrived at the idea of the principle of interaction simultaneity, which states that when two neural firing events are interaction-connected, there is no passage of proper time along the world-line of interaction.

I argue below that the principle of interaction simultaneity is instrumental in accounting for several apparent properties of
our psychological time. The relation of interaction simultaneity to the concept of causality, a fundamental assumption behind all natural laws, will be looked into. Then I would discuss how this principle can account for some characteristics of the psychological flow of time, such as the duration of the specious moment, and the apparently smooth flow of time from the past to the future.

(Translated from the Japanese text of Ken Mogi's "Qualia and the Brain" (Nikkei Science, Tokyo, 1997) by the author)

Tuesday, January 09, 2007

The Dog and the violet

Let us take a specific example. Suppose I was watching a dog. I observe that the dog has white hair, that the ground below the dog is covered with violets, and that the dog's ears are triangular. Here, I presume that the dog, hair, violets, etc. are out there, and I am perceiving something that is outside me. I presume, that I perceive these things as a result of the causal connection that begins with the reflectance of sunlight from the surface of these objects, via the activation of photoreceptors in my retina, and finally the firing of the neurons in my brain.

In a sense the statement "I perceive something that is outside me" is true. But in another sense, this statement is misleading. Everything that I perceive, the dog, the white hair, the violets, are nothing but phenomenological "apparitions" caused by the neural firing in my brain. Thus, the bottom line is, the perceived image of the dog is not outside me, but "within" me. Everything I perceive, even the image of a star billions of light years away seen through a telescope, is nothing but the result of neural firing in my brain.

Even if there is a "dog" standing in a field of "violets", if the neurons in my brain do not fire in an appropriate way, I would not perceive the dog nor the violets. Conversely, even if the "dog" and "violets" were not there, if the neurons in my brain fired in an appropriate manner, I would have a perception of the dog and the violets. We thus come to a very important conclusion. The entities outside me, and my perception of these entities, are in principle separate things. It is only that in normal circumstances, a highly reliable correlation is expected between the external entities and my perception of them. (Otherwise there would be no survival value for perception!) In principle, my perception could be independent of the actual external objects that normally invoke it.

Here, it is important to note that we are not discussing merely a distinction between the real and the virtual. To be sure, if we remain in the domain of anecdotes and analogies we will be unable to deduce any scientifically meaningful conclusions. It is only when we begin to address the serious questions about the neural basis of perception that we realize how much is at stake. In the following argument, it will be shown that the thesis "my perception is a part of me" is something more than a harmless philosophical analogy. It has implications that cuts deep into the very foundations of neuropsychology as is understood today.

(Translated from the Japanese text of Ken Mogi's "Qualia and the Brain" (Nikkei Science, Tokyo, 1997) by the author)

Monday, January 01, 2007

Feeling as if eternal

In youth one feels that one's life would extend for ever. In actuality, however, as we all know, the mortality rate for humans is 100 percent. "Memento Mori" said an old Latin phrase. The young are happily and sometimes tragically oblivious of this warning.

The psychology of this forgetfulness is rather poignant. In good health, we feel as if there's always a "next" day. Just as in natural numbers you can always conceive the "next number" no matter what number is given, in life it feels as if there is always the next day. In the finer scale, you feel as if there's always the next moment. Thus, in mathematical terms, a virtual potential infinity is incurred. The young and healthy can forget the inevitable death because they are living in the potential infinity.

Protention and retention are the basic building materials of our sense of the passage of time. It is interesting to speculate how the phenomenal experience of the specious present is somehow converted into an illusory feeling of eternity. In fact, it is probably the case that the very notion of the infinite or the eternal originated from the sense of potential infinity that accompanies the phenomenal experience of the psychological moment.

As it stands, thoughts about the potential infinity is not sufficiently separated from that of actual infinity. An argument must somehow be found which explains why a virtual potential infinity is incurred in the human psyche although in real terms the life span is necessarily very finite.

There is a potential infinity even in the course of a day, although in this particular case we have a cognitive process of imaging the "end of the day" through our past experience. It is the lack of the knowledge about when one's end is going to come that makes the potential infinity associated with the whole life qualitatively different from the one associated with a particular day.