The Clockwork Universe
The Reversal of Doubt
a) Clear and Distinct Ideas: Meditations I–IV: These are the clear and
distinct, rationally self-evident ideas he has used
1. I exist as a thinking thing (Cogito ergo sum; proof)
2. the test of truth is that what is clearly and distinctly perceived is true
(3 + 2 = 5)
3. only substances exist independently (as does my mind, a thinking
substance)
4. qualities, states, or attributes can exist only as states or attributes of
substances (thinking can exist only as a state of a thinking thing, a
thinking substance)
5. something cannot come from nothing
6. nothing can exist without a cause (a clock could not exist without a
maker)
7. the cause must be as real and as powerful as the effect
8. the more perfect cannot come from the less perfect (so, according to
Descartes, the ideas of a perfect God could not come from an
imperfect human being)
9. God exists as a completely perfect being and is selfcaused, not caused
by or dependent upon anything other than Himself
10.since God is perfect and not a deceiver, clear and distinct ideas,
including those of mathematics and logic, which appear to be
absolutely true, can be known to be absolutely true
Proof of the Existence of Physical Substance
Descartes says various experiences gradually ruined all my faith in the senses.
judgments based upon the external senses (such as sight) were erroneous
huge statues seen from a distance look tiny
square towers appear round
Internal senses are also deceptive: I have heard that people with amputated
limbs sometimes feel sensations in them
Descartes asks what could be the cause of my idea of a physical body?
Could I myself be the cause of my idea of physical bodies? But I cannot be
the cause. The size and shape of my body, the town, the people, the sun, the
fields—all these ideas of bodies were passively received by me. They do not
depend upon my willing them. In fact, these ideas of bodies often occur
contrary to my will.
I could not be the cause since I am a thinking substance. In as much as the
effect must be like the cause, the cause of the idea of physical substance
must be itself a physical substance.
Whether God could be the cause of this idea. But then He would be
deceiving me in allowing me to have a strong inclination to believe that the
cause of these ideas is in physical things.
So, the conclusion is that physical things—material objects—must really exist
outside of us because they're the cause of the ideas we have of them.
In simpler terms: We know physical things are real because we experience
them, we don't control them, and they seem to come from something real and
physical, not just our minds.
“But this does not mean,” says Descartes, the rationalist, hastily, “that material
bodies exist exactly as our senses show them to be.” It is only my clear and distinct
idea of physical things that can tell me what their true nature is.
The Piece of Wax
Descartes wanted to understand what makes something the same thing even when
it changes. He used a piece of wax as an example. At first, it was hard, cold, and
smelled like honey. But when it was heated, it became soft, hot, and lost its smell.
Even though the wax changed a lot, most people would still say it was the same
piece of wax. Descartes argued that the real properties of something are the ones
that stay the same, even when other things change. He said the only things that
stayed the same about the wax were that it took up space and could change.
Descartes believed that the only real, objective qualities of physical objects are the
ones that can be measured and described in terms of space and motion. These
include things like size, shape, and the ability to move.
He argued that other qualities, like color, taste, and smell, are subjective and
depend on our senses. A physical object can still exist without these qualities. For
example, the wax could lose its color, smell, and taste, but it would still be a
physical thing as long as it still had size and shape.
In other words, Descartes thought that physical things need to have size and shape
in order to be physical things at all, but they don't necessarily need to have colors,
tastes, or smells.
By denying the objective reality of secondary qualities and insisting that the
only qualities of physical objects are the spatial qualities of size, shape, and
the capacity of motion, Descartes limited the properties of matter to those
which scientists could measure, quantify, and explain by mathematics.
Mechanism: The Clockwork Universe
Descartes’s theory of the physical universe is called mechanism
Mechanism is the theory that all of nature can be explained by the
mechanical motion of material substances
the world is infinite in extension, with bodies of all shapes and sizes
continually moving and changing
All motion of bodies is due to mechanical impact, like the mechanical
workings in a clock
This is what the physical universe is for Descartes: a mechanical clockwork
system of bodies in motion according to the laws of physics
Descartes’s ( called Behaviorist) Theory of Animals as Mechanical
Clockworks:
Animals are automata, mechanically responsive to the stimulus of other
bodies.
He denied that animals have reason, intelligence, mind, or any inner mental
states.
Such feelings as they have arise only from the mechanical motions of their
bodies.
Descartes reduced animals to being nothing but matter in motion.
Descartes claimed that if machines were constructed to look like animals, we
could not tell them apart.
The fact that animals cannot use language to express themselves does not
show that they have less reason than human rather that they have none at all
as it does not take a lot of effort to be required to talk
It is nature which acts in them according to the disposition of their organs
Opp to this theory is the Darwanian theory of evolution
Descartes sees rationality as completely separating humans from animals by
an unbridgeable gulf, Darwinian theory shows no sharp divisions or
separations, but a continuous gradation of capacities and functions, from the
lowest living organisms to those of the human species.
Opposition of Descartes View:
Recent scientific experiments have focused upon the intelligence of various
animal species, and have shown that one of Descartes’s automata, the
porpoise, is a creature of high intelligence, capable of communicating with
humans.
many people who love and honor animals for their moral qualities of
innocence and lack of hypocrisy, while condemning humans for their
hypocrisy and lack of innocence oppose Descartes view.
Descartes’s Theory of Physical and Mental Substances
Substance: A thing which so exists that it needs no other thing in order to exist.
Only God can be substance in this strict sense. All other substances require God to
exist.
Thinking Substance: Mind, thinking substance, occupies no space; is not in
motion; is not part of any clockwork; has the capacity for reasoning,
remembering, denying; has free will and is morally responsible for its action.
Physical Substance:
Matter takes up space (it has size and shape). It moves because of mechanical
forces (things pushing or pulling on it).
Matter can be divided into smaller and smaller pieces.
It doesn't make decisions on its own; it moves based on how other things act on
it.
Matter doesn't have the ability to think, reason, or have emotions.
It also doesn't have free will or a sense of right and wrong.
The two are independent: the mind doesn't work like matter, and matter doesn't
work like the mind. This means that they need to be studied separately.
Matter is studied by physics, the science that looks at how things move and
interact (like what scientists like Copernicus and Galileo worked on).
The mind is studied by theology (the study of God and religion) and
philosophy (the study of ideas and thinking).
