One of
the greatest mysteries of both philosophy and science that has yet to
be solved is how consciousness happens... and what happens when it
goes wrong. With all our advances we still really don't know how the
brain and body give rise to consciousness. Billions of neurons in
the brain are working together to generate a conscious experience –
not just any conscious experience, but your own individual experience
of the world around you and of yourself within it. So how does this
actually happen?
We
experience joy and suffering; do other animals? Do they have a sense
of self as well? If you have pets you have some sense of the answer.
And what about plants? And as computers get smarter and faster, will
there come a time when your iPhone develops a sense of its own
existence?
The
prospects for a conscious AI are probably pretty remote because
consciousness has less to do with pure intelligence and more to do
with our nature as living and breathing organisms. Consciousness and
intelligence are different things. You don't have to be smart to
suffer, but you probably do have to be alive.
Consciousness
involves both awareness of the self and awareness of the world.
Think of your brain in its bony skull, trying to figure out what's
out there in the world. There's no light or sound inside the skull.
All the brain has to go on are streams of electrical impulses which
are only indirectly related to things in the world. Perception
becomes a form of informed guesswork in which the brain combines
these sensory input signals with its prior beliefs and expectations
about the way the world is to form its best guess about the cause
behind the signals.
The
brain doesn't perceive anything directly nor does it interpret the
world around it entirely from signals coming in from the outside
world. It depends as much, if not more, upon perceptual predictions
based upon experience flowing within it. We don't just passively
perceive the world, we actively generate it. The world comes as
much, if not more, from the inside out as from the outside in.
Our
conscious experiences of the world around us and of ourselves within
it are kinds of controlled hallucinations that happen because we are
alive. Hallucinations are a kind of uncontrolled perception.
Perceptions could also be looked upon as a controlled hallucinations,
in which the brain's predictions are being reigned in by sensory
information from the world.
We are
all hallucinating all the time, including right now. When we agree
about our hallucinations, we call that reality. When someone's
hallucination varies enough from the norm, we call that illness.
Your experience of being your self is a controlled hallucination
generated by your brain. What if you are fooling yourself with your
own self hallucination? How would you know?
Visual
illusions can deceive the eyes and therefore the brain. All of us
can be fooled by a good magician. But how can you be deceived about
what it means to be you? Most of the experience of being a person is
so familiar and so unified and so continuous that it is difficult not
to take it for granted. But we shouldn't take it for granted. All
the ways we look at ourselves as a unique self can come apart. The
identity of the self in the brain is of rather fragile construction.
Even the brain's idea of what the self is is a matter of a best
guess, a kind of controlled hallucination.
The
way we perceive the world outside is quite different than the way we
perceive ourselves. The outside world is perceived as a bunch of
objects; even the body is an object, a thing. But we don't perceive
the world within us as objects – unless we have problems. We know
we have a heart and kidneys and a spleen, but we we don't sense them
as objects. Perception of the internal state of the body isn't about
figuring out what is there, but about control and regulation – much
of it autonomically – keeping our physiological variables within a
narrow range of conditions to continue our survival.
When
the brain uses predictions to figure out what is going on, we see
that objects are the cause of sensations. When the brain uses
predictions to control or regulate we experience how well or how
badly that control is going. So most basic experiences of being a
self or being a body organism are deeply grounded in the biological
mechanisms that keep us alive.
Our
conscious experiences of both the world and our self, since they
depend on the identical mechanism of predictive perception, all stem
from this basic drive to stay alive. We experience the world and
ourselves with, through, and because of our living bodies. We
literally predict ourselves into existence.
There
are several implications here. Just as we can mis-perceive the
world, we can mis-perceive ourselves when the mechanisms of
prediction go wrong. Understanding this opens many new avenues in
psychiatry and neurology because we can finally get at the mechanisms
instead of just treating the symptoms, especially with conditions
like depression and schizophrenia.
What
it means to be me cannot be reduced to or uploaded to a software
program running in a robot, no matter how advanced. The biological
mechanisms that define us depend upon a living, breathing biology.
Just making computers smarter is not going to make them sentient.
Finally,
our way of being conscious is likely just one possible expression of
being conscious. Human consciousness is just one example in a vast
array of possibility in a very, very large universe. With the
application of quantum thinking, a growing wealth of research
suggests that not only do all living things have some form of
conscious awareness, but so might all inanimate matter and energy as
well. We must be careful to leave the door of possibility open to
all manner of perceptual predictions, both on our own planet and
beyond.
Understanding
the biological basis of conscious experience is one of the great
challenges for 21st-century science. As with life, so with
consciousness, once we start explaining its properties in terms of
things happening inside brains and bodies, the apparent insolubility
of what consciousness is starts to fade away.
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