1. Do people have
freewill?
Decide!

2. Psychology
Debate:
Materialism vs. Dualism
Determinism vs. Freewill

3. The debate then & now
 Psychology still wrestles with the old
philosophical debate of freewill vs.
determinism , which grew out of an even
older debate over the soul called
materialism vs. dualism

4. Dualism:
 Each human being consists of two distinct
but conjoined entities, a material body and
an immaterial soul
– The body is part of the natural world
– The soul is supernatural

5. René Descartes (1596-1650)
Dualist
 Believed that the body is a
machine and can operate
without the soul- the bodies
of animals are soulless
machines
 Said that thoughts are the
one function of the soul
because humans, and not
animals, have them
 Equated the idea of soul
with the idea of a mind

6. Materialism
 Each human being consists of nothing
more than a physical body.
 There is no limit to what can be physically
studied

7. Thomas Hobbes (1588-1679)
Materialist
 Said that the spirit, or soul,
is a meaningless concept
and nothing exists but
matter and energy
 All the seemingly voluntary
choices we make are
actually physical
processes of the body
 Conscious thought is
purely a product of the
brain’s machinery

8. Freewill
 Humans are free to choose their behavior
 Can reject influences (biological or
environmental) at will

9. Determinism
 Every physical event is caused, and, since
human behavior is a physical event, it
follows that it too is caused by preceding
factors
 If perfect knowledge is gained of the
current state of the universe, then future
events are entirely predictable

10. Freewill
Pros - Cons
 Used in Humanistic and  Pure freewill is
cognitive psychology incompatible with the
 Introspection on our assumptions of science
decisions seems to  It is difficult to define
indicate freewill what freewill is and
 Even if humans do not what the self is that
have freewill, the fact does the choosing
that they think they do  The evidence of the
has many implications existence of freewill is
for behavior mostly subjective

11. Determinism
Pros - Cons
 Used in Behaviorism,  Determinism is
sociocultural, inconsistent with
psychodynamic and society’s ideas for self
biological psychology control and
 Mental disorders seem responsibility
to indicate a lack of  Can never lead to
freewill complete prediction
 Determinism is a key  Is unfalsifiable since it
assumption of science- always assumes a
which seeks laws of cause exists, even if
cause and effect one has not been found
yet