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William James
What role does consciousness play
in choosing an intended action?
What role does consciousness play
in Darwinian evolution?
The problem is this: If we assume that all mental processes are determined by
physical processes, how can consciousness -- which surely is the result of brain
activity -- exert any influence on neural mechanisms or on behaviour which
then becomes ‘visible’ to natural selection?
The alternative view, expressed by Thomas Henry Huxley (1825-1895) was that
consciousness is merely an epiphenomenon. In other words, consciousness plays no causal role
in behaviour but is much like the steam emitted by an engine -- the result of its operation,
having no conceivable functional role.
William James was opposed to this view of consciousness as causally inert. Rather, he inferred that
conscious mental life exerted a direct influence on the activity of the central nervous system.
Are we automata -- was a rebuttal of a lecture presented by Thomas H. Huxley in a famous address
he (Huxley) delivered in Belfast, 1874, entitled "On the Hypothesis that Animals are Automata,
and Its History".
The theory maintains that in everything outward we are pure material machines. Feeling is a mere
collateral product of our nervous processes, unable to react upon them any more than a shadow reacts
on the steps of the traveller whom it accompanies. Inert, uninfluential, a simple passenger in the voyage
of life, it is allowed to remain on board, but not to touch the helm or handle the rigging.
By contrast, James argued that ‘Consciousness .... has been slowly evolved in the animal series, and resembles
in this all organs that have a use’
For complex (high) brains:
the brain ‘...is as likely to do the crazy as the sane thing at any
given moment. A low brain does few things, and in doing
them perfectly forfeits all other use. The performances of a
high brain are like dice thrown forever on a table. Unless they
be loaded, what chance is there that the highest number will
turn up oftener than the lowest?’.
The advantage to such unpredictability in a complex brain is that the animal is potentially
adapted to respond to a very large number of different challenges imposed by its
environment.
James then asks the question: Can consciousness increase the
adaptive function of the brain’s responses by ‘loading the dice’ in
favour of one brain state as opposed to another?
James described Darwin’s idea: ‘The mechanical processes of "spontaneous variation" and
"natural selection" bring about ...(their effects)... by their combined action; but being physical processes
they can in no sense be said to intend it.
As we have seen, Darwinian evolution does not work by specifying an intention or
purpose guiding natural selection. But consciousness does work purposefully, by striving
to maintain the welfare of the conscious individual.
‘The followers of Darwin rightly scorn those teleologists who claim that the physical process.... of
evolution follows an ideal of perfection....But now suppose that ....the consciousness of the creature itself
postulates survival as its ...(most important goal...), and by its cognitive faculty recognizes as well as Mr.
Darwin which of its actions and functions subserves this good.’
James on competing affordances
We use the term ‘affordance’ when referring to the actions available to an animal given
a) the situation it faces
and
b) the animal’s particular physical capabilities.
For example, a vine of suitable thickness hanging from a tree would affords climbing, swinging,
or tugging (say, to bring the branch down lower if it contains fruit) to a creature with the right
physical and mental attributes (the vine will not have these affordances, for example, to a turtle).
Any object or situation entails multiple affordances
DOES A WINEGLASS HAVE
THE SAME AFFORDANCES
FOR A HUMAN AND A GOAT?
How does perception lead to voluntary action?
Recall there were three ways of acting.
Descartes
According to this view (Descartes’), by the time motor processing begins, cognitive processes have
arrived at a decision on what to do, and only a single motor program is prepared before movement
initiation.
Modern neurophysiological evidence does not support this view of action. Instead, the motor
system immediately computes multiple options for responding (i.e. motor affordances) in parallel
(meaning, they are computed at the same time). One of these options eventually wins out over the
other choices, given our goals or task set.
The affordance competition hypothesis
Task set: Propose a toast
Select this grasp
We see that the mind is at every stage a theatre of
simultaneous possibilities.
William James
An act has no ethical quality whatever unless it be chosen
out of several all equally possible.
Looking back then.... we see that the mind is at every stage a theatre of simultaneous possibilities.
Consciousness consists in the comparison of these with each other, the selection of some, and the suppression
of the rest by the reinforcing and inhibiting agency of attention.
(ii ) An act has no ethical quality whatever unless it be chosen out of several all equally possible. To sustain
the arguments for the good course and keep them ever before us, to stifle longing for more flowery ways, to keep
the foot unflinchingly on the arduous path, these are characteristic ethical energies.
Attention is not simply captured by the strongest affordance from amongst competing
possibilities for action, it must be actively directed by our conscious will. As James put it, we
do not will what we do. Rather, we do what we will.
We are often in situations where the strongest, most routine affordance is the one
we must resist if we are to make the choice consistent with our intentions.
As James argued, ‘The strongest tendencies to automatic activity in the nerves often run most
counter to the selective pressure of consciousness. Every day of our lives we struggle to escape some
tedious tune or odious thought which the momentary disposition of the brain keeps forcing upon
us.’
Darwin argued that ethical decisions were generally determined by biological principles
that did not require the added notion of free will.
James disagreed with this view that ‘...with a given fixed character only one reaction is possible
under given circumstances’.
Instead, he argued that in the battle to reach a difficult decision amongst competing
alternatives, what is at stake is our conscious sense of self, both of our present self and the
self we might wish to become.
The idea behind James’ ... point is that
consciousness -- via the mechanism of attention -is intimately involved in selecting from competing
options.
JAMES’ VIEW OF ACTION
VS.
LOCKE’S VIEW OF ACTION
JAMES ARGUED THAT…..
we do not will what we do. Rather, we do
what we will.
HOW DOES THIS VIEW DIFFER FROM LOCKE’S?
WHAT SELECTS FROM COMPETING URGES, ACCORDING
TO LOCKE?
WHAT SELECTS FROM COMPETING URGES, ACCORDING
TO JAMES?
The competition between different choices may occur
unconsciously but at some point, our will is determined by
‘the most.....urgent uneasiness’ we in fact perceive.
So a conscious intention is a particular kind of mental state
that emerges after competing possible desires are resolved in
favour of one dominant goal.
Looking back then…. we see that the mind is at
every stage a theatre of simultaneous possibilities.
Consciousness consists in the comparison of these
with each other, the selection of some, and the
suppression of the rest by the reinforcing and
inhibiting agency of attention.
Attention leading to action is directed by our will, rather
than being automatically controlled by external events.
This view is also different from the one expressed by
Darwin, who argued that ethical decisions were generally
determined by biological principles that did not require the
added notion of free will.
James disagreed with this view expressed by Darwin that
‘...with a given fixed character only one reaction is possible
under given circumstances’.
Instead, he argued that in the battle to reach a difficult
decision amongst competing alternatives, what is at stake is
our conscious sense of self, both of our present self and the
self we might wish to become.
The material self, which includes our clothes and possessions, and our body.
The social self, or our image of ourselves as reflected in the opinions of others.
And our spiritual self, which is the idea we have of our deepest being.
All of these selves are founded upon a feeling of emotion or self love. We love our different selves as
friends, and so experience a deep motivation to protect them.
Ideomotor theory
Sensory Input
Motor Activation
Kinesthetic
Activation
Motor Execution
How do the sensory and motor systems of the brain
communicate with each other?
Our sensory system represents patterns of stimulation
in sense organs.
The motor system communicates patterns of excitation
to muscles.
There is no obvious way in which a motor and a
sensory representation could be directly compared.
The task requires a mapping device that somehow translates the representations of
colours into a representation of the motor commands that control the hands).
Look at the diagram to remind yourself of Descartes’ view.
The pineal gland was the location of the ‘central station’ that translates
between perception and action.
Surprisingly, this view has come to dominate modern
psychology.
Perception and action are presumed to have fundamentally
different representations which serve distinct functions in
mental life.
Perception
Action
William James had a very different view of the
relationship between perception and action.
Ernst Mach, a 19th century physicist who was also
interested in the question of how we act on what
we perceive, illustrated this view in the diagram on the right.
What then is the difference between a self generated
action and other perceived events?
According to ideomotor theory, voluntary actions are represented
in the same format as other perceptual events.
We can distinguish our self-generated motor events from other
perceptual events because our actions are triggered by a knowledge
of:
an anticipated sensorimotor (or kinaesthetic) experience of an
intended action.
and
the external (or physical) outcome of the action.
Ideomotor Theory:
A voluntary action is initiated by actively anticipating a particular sensory
(kinesthetic) effect.
This will spread activation to, and thus gain control over M, which makes the
resulting action voluntary.
Sensory Input
Motor Activation
Kinesthetic
Activation
Motor Execution
Modern evidence that action and perception share
common representations.
James’ theory of emotion in relation to his
ideomotor theory of action.
An emotion, according to James, depended on an instinctive
pattern of internal and external responses to a perceived event.
Human beings do not differ from animals in having fewer such
instincts.
On the contrary, we ‘...are more richly endowed in this respect
than any other mammal’.
Perception
Emotions
Instinctive
Action
Routines
Feelings/
Sensations
‘….. we feel sorry because we cry, angry because we strike,
afraid because we tremble, and not that we cry, strike, or
tremble, because we are sorry, angry, or fearful, as the case
may be.
Without the bodily states following on the perception, the
latter would be purely cognitive in form, pale, colorless,
destitute of emotional warmth. We might then see the bear,
and judge it best to run, receive the insult and deem it right
to strike, but we could not actually feel afraid or angry’.
….we seem immediately faced by this objection: most of the
objects of civilized men's emotions are things to which it would
be preposterous to suppose their nervous systems
(...innately...) adapted.
Most occasions of shame and many insults are purely
conventional, and vary with the social environment. … And if in
these cases the bodily changes follow the ideas, instead of
giving rise to them, why not then in all cases?
To account for emotions that appeared
to be driven by societal norms (e.g. anxiety
at public speaking):
James argued that an automatic response originally
triggered by biologically relevant events (for example,
the sight of a threatening object) may become
associated, through experience, with other more
complex aspects of our environment.
For example, silent staring is treated by many animals as
a threat. A silent audience staring at a speaker might
produce anxiety for the same reason.
Whistling to keep up courage is no mere figure of speech. On the other hand, sit all day in a moping posture, sigh, and reply to everything
with a dismal voice, and your melancholy lingers. There is no more valuable precept in moral education than this, as all who have experience
know: if we wish to conquer undesirable emotional tendencies in ourselves, we must assiduously, and in the first instance cold-bloodedly, go
through the outward motions of those contrary dispositions we prefer to cultivate. The reward of persistency will infallibly come, in the
fading out of the sullenness or depression, and the advent of real cheerfulness and kindliness in their stead. Smooth the brow, brighten the
eye, contract the dorsal rather than the ventral aspect of the frame, and speak in a major key, pass the genial compliment, and your heart
must be frigid indeed if it do not gradually thaw!
What causal role does consciousness play
in our actions?
Is consciousness an epiphenomenon?
Nicholas Humphreys:
We evolved the ‘thick moment of consciousness”.
Suppose that, at a relatively late stage in human evolution, after the thick moment of consciousness
has already been established as the anchor for the Self, variant genes arise whose effect is to give
the conscious Self just the extra twist that leads the human mind to form an exaggeratedly
grandiose view of its own nature.’
Compare with William James
The followers of Darwin rightly scorn those teleologists who claim that the
physical process…. of evolution follows an ideal of perfection….But now
suppose that ….the consciousness of the creature itself postulates survival
as its …(most important goal...), and by its cognitive faculty recognizes as
well as Mr. Darwin which of its actions and functions subserves this good.’