Computational functionalists such as Daniel Dennett take the further step that, apart
from providing housing for functioning, material stuff is irrelevant. Any system that
functions as-if it has consciousness and mind does have consciousness and mind. If a
non-biological system functions exactly like a human mind then it has a human mind,
as the only thing that makes a system a “mind” is the way that it functions. In its usual
reductionist versions, computational functionalism finesses questions about the
distribution of first-person consciousness, routinely translating these into questions
about how different systems function (see Understanding Consciousness, chapters 4
and 5).
Can one draw a line between things that have consciousness and those that
don’t?
Where then should one draw the line between entities that are conscious and those
that are not? Theories about the distribution of consciousness divide into continuity
and discontinuity theories. Discontinuity theories all claim that consciousness
emerged at a particular point in the evolution of the universe. They merely disagree
about which point. Consequently, discontinuity theories all face the same problem.
What switched the lights on? What is it about matter, at a particular stage of
evolution, which suddenly gave it consciousness? As noted above, most try to define
the point of transition in functional terms, although they disagree about the nature of
the critical function. Some think consciousness “switched on” only in humans, for
example once they acquired language or a theory of mind. Some believe that
consciousness emerged once brains reached a critical size or complexity. Others
believe it co-emerged with the ability to learn, or to respond in an adaptive way to the
environment.
In my view, such theories confuse the conditions for the existence of consciousness
with the conditions that determine the many forms that it can take. Who can doubt
that verbal thoughts require language, or that full human self-consciousness requires a
theory of mind? Without internal representations of the world, how could
consciousness be of anything? And without motility and the ability to approach or
avoid, what point would there be to rudimentary pleasure or pain? However, none of
these theories explains what it is about such biological functions that suddenly
switches consciousness on.
Continuity theorists do not face this problem for the simple reason that they do not
believe that consciousness suddenly emerged at any stage of evolution. Rather, as
Sherrington suggests above, consciousness is a “development of mind from
unrecognizable into recognizable.” On this panpsychist view, all forms of matter
have an associated form of consciousness, although in complex life forms such as
ourselves, much of this consciousness is inhibited. In the cosmic explosion that gave
birth to the universe, consciousness co-emerged with matter and co-evolves with it.
As matter became more differentiated and developed in complexity, consciousness
became correspondingly differentiated and complex. The emergence of carbon-based
life forms developed into creatures with sensory systems that had associated sensory
“qualia.” The development of representation was accompanied by the development of
consciousness that is of something. Once conscious states were associated with the
adaptive, perceptual functioning of numerically distinct, spatially separated organisms