From: J. R. Molloy (jr@shasta.com)
Date: Sun Jan 14 2001 - 21:49:02 MST
Just one of many obsolete questions listed at The Edge.
This is one very fine project!
--J. R.
"The definition of life and consciousness?"
http://www.edge.org/documents/questions/q2001.2.html
Some scientific questions cannot be resolved, but rather are dissolved,
and vanish once we begin to better understand their terms.
This is often the case for "definitional questions". For instance, what is
the definition of life? Can we trace a sharp boundary between what is
living and what is not living? Is a virus living? Is the entire earth a
living organism? It seems that our brain predisposes us to ask questions
that require a yes or no answer. Moreover, as scientists, we'd like to
keep our mental categories straight and, therefore, we would like to have
neat and tidy definitions of the terms we use. However, especially in the
biological sciences, the objects of reality do not conform nicely to our
categorical expectations. As we delve into research, we begin to realize
that what we naively conceived of as a essential category is, in fact, a
cluster of loosely bound properties that each need to be considered in
turn (in the case of life: metabolism, reproduction, autonomy, homeostasy,
etc..). Thus, what was initially considered as a simple question,
requiring a straightforward answer, becomes a complex issue or even a
whole domain of research. We begin to realize that there is no single
answer, but many different answers depending on how one frames the terms
of the question. And eventually, the question is simply dropped. It is not
longer relevant.
I strongly suspect that one of today's hottest scientific question,s the
definition of consciousness, is of this kind. Some scientists seem to
believe that what we call consciousness is an essence of reality, a single
coherent phenomenon that can be reduced to a single level such as a
quantum property of microtubules. Another possibility, however, that
consciousness is a cluster of properties that, most of the time, cohere
together in awake adult humans. A minimal list probably includes the
ability to attend to sensory inputs or internal thoughts, to make them
available broadly to multiple cerebral systems, to store them in working
memory and in episodic memory, to manipulate them mentally, to act
intentionally based on them, and in particular to report them verbally. As
we explore the issue empirically, we begin to find many situations (such
as visual masking or specific brain lesions) in which those properties
break down. The neat question "what is consciousness" dissolves into a
myriad of more precise and more fruitful research avenues.
Any biological theory of consciousness, which assumes that consciousness
has evolved, implies that "having consciousness" is not an all-or-none
property. The biological substrates of consciousness in human adults are
probably also present, but only in partial form, in other species, in
young children or brain-lesioned patients. It is therefore a partially
arbitrary question whether we want to extend the use of the term
"consciousness" to them. For instance, several mammals, and even very
young human children, show intentional behavior, partially reportable
mental states, some working memory ability - but perhaps no theory of
mind, and more "encapsulated" mental processes that cannot be reported
verbally or even non-verbally. Do they have consciousness, then? My bet is
that once a detailed cognitive and neural theory of the various aspects of
consciousness is available, the vacuity of this question will become
obvious.
STANISLAS DEHAENE, researcher at the Institut National de la Santé,
studies cognitive neuropsychology of language and number processing in the
human brain; author of The Number Sense: How Mathematical Knowledge Is
Embedded In Our Brains.
-------------------------------------------------
Stay hungry,
--J. R.
3M TA3
Useless hypotheses: consciousness, phlogiston, philosophy, vitalism, mind,
free will
This archive was generated by hypermail 2.1.5 : Sat Nov 02 2002 - 08:04:53 MST