The innovation that Braitenberg briefly introduces here is the notion of a "pleasure principle" to be used to aid a vehicle in choosing among potential next states.
The root of this innovation is Braitenberg's assessment that his vehicles do not have any personality, because they are not drawn by goals in the same fashion as people. "We cannot help feeling that they are driven by necessity rather than drawn by goals -- in spite of all of the efforts we put into them, in spite of special mechanisms that are apt to abolish lowly forms of causality, and in spite of the predictor that seems to draw motives from a future state of the world."
Braitenberg's goal is to modify a vehicle so that "the pump of thoughts in the brain of the vehicle will produce a succession of more and more pleasurable mental images." Here's how:
"We will assume that most of the time the uncertainty as to the next state, given a certain state of activity, is not only an uncertainty for the observer but an inherent uncertainty in the sense that the predictor points toward (at least) two states that are equally likely...Such a dilemma in previous vehicles might have been decided by a random element." Not so, now. With multiple choices for a prediction, the goal is to choose as the next brain state the state that is most pleasurable. This can be done with all of the mechanisms of the predictor, because the vehicle has some sense of what the next possible states will be, and therefore can evaluate the consequences of being in them before that state is achieved.
(NB: To my mind, this brings an interesting slant on natural computation. In natural computation theories of vision, the system is faced with a number of equally likely interpretations, and then uses additional constraints to choose among them. The choice is made by also requiring the interpretation to be consistent with a set of natural constraints that act to ensure that the chosen interpretation is almost certainly correct. Here, Braitenberg faces a problem of underdetermination, but essentially uses aesthetic constraints to solve it! I wonder if the pleasure principle could be used to derive natural visual constraints?)
The chance element is removed from type 14 vehicles. "They move through their world with consistent determination, always clearly after something that very often we cannot guess at the outset" ... "running after a dream"...this "does seem to reflect a basic attitude of humankind, this irrational belief in the effectiveness of one's own actions."
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