These are excerpts and elaborations from my book "The Nature of Consciousness"
|
Vehicles The Italian
neurophysiologist Valentino Breitenberg proposed a thought experiment
which consists in mentally building progressively more complex machines,
starting with the most elementary ones. At the beginning, there are only
vehicles that respond to their environment. The first vehicle is simply made
of a motor and a sensor: the speed of the motor is controlled by the sensor,
motion is meant to be only forward. But in the real world this vehicle is
subject to friction (where friction is the metaphysical sum of all forces of
the environment) and therefore the trajectory will tend to deviate from the
straight line. In fact, in a pond the movement would be quite complex. That's
the whole point: despite the simple internal workings of these machines, they
seem to be alive. We can increase little by little their circuitry, and at each
step these vehicles seem to acquire not only new skills, but also a stronger
personality. The second vehicle is still
fairly simple: two motors and two sensors. The sensor is designed to get
excited by whatever kind of matter. It turns out that depending on the way they
are wired, these vehicles react differently to the exciting matter: one runs
towards it, while the other runs away from it. One is "aggressive",
the other is "afraid". And so forth. As their
circuitry increases, the vehicles seem to exhibit more sophisticated feelings. By adding simple
electro-mechanical components, Breitenberg induces the machines to reason
logically (via McCulloch-Pitts neurons). As the devices get more complicated, shapes
are recognized; regularities are represented; properties of objects are
discriminated. Hebbian associations
(that get stronger as they are used) allow for concepts to emerge. Soon the machines start exhibiting learning
and memory. Causation (as constant
succession) and attention (as self-control over associations) finally lead to
trains of thoughts. At this point something very
similar to the human mind can be said to be born, and all Breitenberg has to do
is add circuitry for social and moral skills. The leitmotiv of
Breitenberg's research is that it is far easier to create machines that exhibit
"cognitive" behavior simply by interacting with the environment than
it is to analyze their behavior and try to deduce the internal structure that
produces such cognitive behavior. Breitenberg's ideas spawned
an entire generation of robots, which their constructors appropriately tend to
call "creatures". Back to the beginning of the chapter "Ecological Realism: The Embodied Mind" | Back to the index of all chapters |
|
|
|
|