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2 The Visual World
A machine is designed by engineers to carry out a specific function. The
evolutionary process of adaptation and selection is likewise a form of design,
giving rise to biological structures that play an essential role in the survival
of organisms. Hearts develop because they have the indispensable function of
pumping blood to supply the body with nutrients and collect waste. Visual
systems likewise are very specialized organs, and have gradually developed over
great stretches of time to carry out specialized tasks which support the activities
of their possessors.
Eyesight in animals—no less than optical recognition in machines—is pragmatic: To understand vision one must take into account the specific tasks, in a
creature’s daily life, which depend on vision—and in what specific ways vision
is utilized to carry them out. Eyesight did not evolve in order for creatures to
enjoy “pure vision”—that is, to see for the sake of seeing. Rather, what creatures
see, and especially how they see it, is a complex adaptation to practical needs.
The quality of animal vision surpasses Shakey’s by leaps and bounds, yet it
is grounded on the same pragmatic basis: Vision brings environmental information home to us in response to explicit needs, and is precisely co-ordinated
with those needs. The heart is not an all-purpose pump, legs are not all-purpose
walkers, and eyes are not all-purpose peepers.
Do We See the World Realistically?
The cognitive scientist Donald Hoffman of the University of California in San
Diego has published an influential theory on visual perception which sheds
further light on what is stated above. Hoffman begins with the Darwinian
premiss that evolution designs organisms so they are the fittest possible in their
environment: The principle of maximizing fitness applies to organs, to behavior, and also to the way creatures picture the world in awareness. A particular
way of picturing objects in the mind will be selected by evolution if it is the
most effective way of allowing the animal to make rapid and correct decisions. 4
What Hoffman claims is that the way objects appear to us is dictated by
considerations of fitness and not realism. What an animal experiences seeing
may be unlike a high-fidelity reproduction of reality, with all its complexity
and inscrutability—yet it may be far more helpful when the animal needs to
size up the current situation correctly and act appropriately. The claim is that
so long as all the experiences a creature has with objects are consistent with
one another—with no discrepancies of any kind—the creature is far better off
interacting in mind with usefully simplified and schematized replicas.
2 The Visual World
A machine is designed by engineers to carry out a specific function. The
evolutionary process of adaptation and selection is likewise a form of design,
giving rise to biological structures that play an essential role in the survival
of organisms. Hearts develop because they have the indispensable function of
pumping blood to supply the body with nutrients and collect waste. Visual
systems likewise are very specialized organs, and have gradually developed over
great stretches of time to carry out specialized tasks which support the activities
of their possessors.
Eyesight in animals—no less than optical recognition in machines—is pragmatic: To understand vision one must take into account the specific tasks, in a
creature’s daily life, which depend on vision—and in what specific ways vision
is utilized to carry them out. Eyesight did not evolve in order for creatures to
enjoy “pure vision”—that is, to see for the sake of seeing. Rather, what creatures
see, and especially how they see it, is a complex adaptation to practical needs.
The quality of animal vision surpasses Shakey’s by leaps and bounds, yet it
is grounded on the same pragmatic basis: Vision brings environmental information home to us in response to explicit needs, and is precisely co-ordinated
with those needs. The heart is not an all-purpose pump, legs are not all-purpose
walkers, and eyes are not all-purpose peepers.
Do We See the World Realistically?
The cognitive scientist Donald Hoffman of the University of California in San
Diego has published an influential theory on visual perception which sheds
further light on what is stated above. Hoffman begins with the Darwinian
premiss that evolution designs organisms so they are the fittest possible in their
environment: The principle of maximizing fitness applies to organs, to behavior, and also to the way creatures picture the world in awareness. A particular
way of picturing objects in the mind will be selected by evolution if it is the
most effective way of allowing the animal to make rapid and correct decisions. 4
What Hoffman claims is that the way objects appear to us is dictated by
considerations of fitness and not realism. What an animal experiences seeing
may be unlike a high-fidelity reproduction of reality, with all its complexity
and inscrutability—yet it may be far more helpful when the animal needs to
size up the current situation correctly and act appropriately. The claim is that
so long as all the experiences a creature has with objects are consistent with
one another—with no discrepancies of any kind—the creature is far better off
interacting in mind with usefully simplified and schematized replicas.