These are excerpts and elaborations from my book "The Nature of Consciousness"
Brains Cause Minds The state of the “mind-body
debate” can be appreciated by vivisecting some of its fundamental tenets. Many contemporary
philosophers, notably John Searle, would subscribe to the statement that minds are caused by brains. And
the notion sounds intuitively true. A closer inspection reveals how unfounded
this view is, and how misleading it can be for reasoning on consciousness. The
problem is that the sentence is too informal to yield any formal, scientific
discussion. First of all, is the brain
sufficient for a mind to exist? Can a brain alone yield a mind? We have no
evidence whatsoever of a brain that, alone, causes a mind. Without a heart,
would the brain cause a mind? Without the blood? Without the oxygen? Without
all the nerves connecting to the senses? If somebody were to cut my head off
and pull my brain out, I doubt that my brain would still cause my mind to
exist. It would still be made of exactly the same matter, but it would not be
able to cause a mind anymore. It would be, quite simply, rotting. The same
object causes a mind or not depending on whether it is alive or dead. Truth is,
we only have evidence of minds contained in bodies, and in living bodies.
Therefore, it would be more appropriate to state that “living bodies cause
minds”. Second, is the brain
necessary for a mind to exist? We have no evidence of other (non-brain) things
causing minds, but then we have no way of gathering that evidence. There is no
way that we can know whether a different type of thing can also cause a mind.
There is no way of knowing if an insect is conscious, if bacteria are
conscious, if plants are conscious, if crystals are conscious, etc. Therefore,
it would be more prudent to say that “at least living bodies cause minds”.
Which is a far less exciting proposition than “brains cause minds”. But the biggest problem is
that even the term “brain” needs to be qualified. What is a brain? Is the skull
part of the brain? Are the eyes part of the brain? What are the borders of the
brain? Where does a nerve stop being part of the brain? Where do we cut off all
the nerves, veins and muscles that link it to the rest of the body? At the
chin? At the throat? How much can we change in a brain without changing its
being a brain? What about other animals? Do cat’s brains also qualify as
brains? Do nervous systems of insects also qualify as brains? Does a computer
qualify as a brain? Does a crystal qualify as a brain? What makes a brain a
brain? If minds are indeed caused
by brains, what needs to be present in a conglomerate of neurons for it to
become a brain that causes a mind? As a hypothetical Dr Frankenstein adds
features to the ball of fibers that he assembled in his laboratory, at which
point does that ugly mess become a mind that feels and thinks? The closer we look, the less
sure we are of the intuitive statement that brains cause minds. Back to the beginning of the chapter "Mind and Matter" | Back to the index of all chapters |