Cartesianism is so-called because
as a way of perceiving the world it derives from the philosopher
Rene Descartes (1596-1650). He's considered by many as the founder of
modern philosophy. Bertrand Russell 
thinks that Descartes was the first thinker since Aristotle to work de
on the nature of knowledge.
It may be helpful to put Cartesianism in a broader
context, lest its concerns seem largely pointless to the contemporary
person. One of the roots of the way Descartes analysed reality goes back
to Plato. The latter concluded that the world we experience is surely too
imperfect to be the best there is. Since we can conceive of perfection
there must be an over-arching realm or second dimension in which
unchanging perfection rules.
This idea of a
two-world reality was the way almost everyone in the 16th and 17th centuries
thought of their universe. Most religions reflected the idea in terms of a
dimension inhabited by God or gods on one hand, and the dimension we inhabit
on the other. The art of religion was to attain satisfactory communication
between the two. It also facilitates our passage, given certain conditions,
from this world into the next.
Ideas of revelation rested on the proposal that God
communicates with us from the higher of the two dimensions. Knowledge
gained in this way can't of course be contradicted or even doubted, since
it originates from God. God must be perfection itself or, as some put it,
the "absolute". From there it was but a short step to insist that doubt
itself is a betrayal of truth, since God cannot but tell us only what is
Descartes was a gifted thinker of independent means who
asked the question, "What happens if I doubt everything?" Throughout his
life he wisely avoided being too public with his answers because the
various ecclesiastical authorities could turn nasty if they thought that
doctrinal verities might be at risk from innovative thought.
Descartes' position was predicated by the tacit
assertion that answers to his questions were determined by rational
thought rather than authority based on revelation. Rationality thrives on
doubt, revelation on certainty. This was nothing short of revolutionary in
an age when infallible authority ruled the roost. It should be remembered
that the 16th century was a time of rigid social structures and codes.
Both secular and ecclesiastical powers could, and did, heavily penalise
and even kill dissenters.
Descartes argued that the possibility exists that we are
deceived in what we think is true and real. "Can I doubt that I'm sitting
in front of a fire in my dressing gown?" he asks. The answer is yes,
because I could in fact be lying in bed and dreaming that I was sitting in
front of the fire. On top of that, says Descartes, we all know that it's
possible to have delusions. I might be in a mental hospital imagining the
Of what, then, can you or I be certain? If I can doubt
even my experience of reality, is anything left of certainty? Even
revelation might be a delusion. My very existence might be a delusion in
someone else's mind.
But we have to stop there,
says Descartes, because if I don't exist then I can't be deluded. So
something called "me" must exist in some way or other. But, taking
"Cartesian Doubt" as far as possible, it might be that my body and what I
call its sensations are illusions.
This leaves what
Descartes called "soul" or "mind". One day, sitting next to his stove, he
came up with a proposal which seemed to solve the problem of existence. He
While I wanted to think everything false, it must
necessarily be that I who thought was something; and remarking that this
truth, I think, therefore I am, was so solid and so certain that
all the most extravagant suppositions of the sceptics were incapable of
upsetting it, I judged that I could receive it without scruple as the
first principle of the philosophy that I sought.
Here at last, he thought, is the bedrock upon which it
might be possible to build a new, non-revelatory, way of knowing the world
and everything. That mind or soul is more certain than matter (a
conclusion known as "subjectivism") became the foundation of a whole new
way of thinking.
Like every new proposal,
Cartesianism has its special problems. If the existence of matter (our
bodies, chairs, other people, the universe) is knowable only by inference
from the mind or soul is there any point in so inferring? Does it matter one
way or the other if the cat I'm stroking is really there? Does it matter if
I stroke it or kill it?
Mathematics and geometry may
be different, however. Even in dreams and delusions 2 + 2 = 4 and a right
angle is 90 degrees. That is, they seem to be a type of knowledge
independent of mind and the world.
however, is establishing why I should think I'm stroking a cat rather than a
man-eating lion. An easy answer might be that the two give entirely
different sensations. But why should sensations be real, and the cat and
lion be delusions? If the mind can experience sensations, and the sensations
are real, there surely the objects which cause the sensation must be real?
Can I really doubt the lion's existence and suppose that I'm being
torn apart by a household cat?
nevertheless maintained that, strictly speaking, knowledge of "external"
things is by the mind not the senses. Descartes used the analogy of wax. It
has certain characteristics when cold. But that doesn't mean that it ceases
to be wax when it's hot and runny. This shows that the reality "wax" must be
known by something other than the senses. We call that thing the mind or
soul. It's important to note, however, that the wax Descartes used for his
analogy might not be real in the first place.
should by now be evident that despite a neat bit of reasoning, Cartesian
conclusions tend to lose relevance as soon as one attempts to come to grip
with external things which may or may not exist.
Descartes proposed a solution which seemed entirely plausible in his time.
He proposed that the soul resides somewhere - in the pineal gland (Descartes
was interested in medicine and knew the human anatomy well). There the soul
contacts "vital spirits" - a sort of life force which penetrates
The body itself, like all animals
(which have no souls), operates automatically. The pineal gland provides an
interface between the body and the vital spirits. It allows the soul to
interact with the world. I suppose that Descartes and other thoroughgoing
Cartesians would continue to maintain that the physical body containing the
pineal gland might be an illusion. And it's difficult to know why they
bother with such devices if only the soul is real. Only the soul can move
and change. So what point is an interface if bodily behaviours are
cogito ergo sum ("I think therefore I am") answer is too slick.
Perhaps Descartes need not have worried so much about the ecclesiastical
authorities. As it happened, the Christian churches and theologians seem to
have rather liked his conclusions because they preserve the idea of an
immortal soul. Traditional theology demanded that something be left over to
ascend to heaven after physical death.
scientific theories about the sun and earth, amongst other theories, were
not much noticed by the wider scientific audience of his day. Those who did
notice, quickly demolished them.
Descartes and the
early Cartesians thought that only the soul could experience "movement" -
what we'd today most probably call change or perhaps entropy (Boltzmann's
Second Law of Thermodynamics). The physical world is governed by rigid,
unchanging laws. This conclusion was necessary because in their scheme of
things the soul had to be ultimately independent of the body. Only the soul
was real and therefore open to modification or "movement".
Isaac Newton was born two years after Descartes' death. His work had major
effects on the Cartesian scheme. First, it virtually destroyed Cartesian
physical science, based as it was on incomplete mathematics and uncertain
experiments. Descartes applied algebra to geometry, for example, using
co-ordinates to fix the position of a point on a plane. But although he made
a useful start, it was left to later thinkers to perfect what he began.
Second, Newtonian theory cemented into the Western mind the idea that nature
is ruled by inflexible physical laws. Cartesian determinism - the idea that
mind and matter don't effectively interact, that choices have no effect in a
mechanistic physical world - was thus strengthened. There were incalculable
social consequences which echo through history to this day, particularly
when linked with crude Darwinism.
One aspect of the
scientific method was strengthened by Descartes. His method of scientific
analysis contained the basic assumption that problems are best solved by
breaking them down into their constituent parts. Later this became known a
"reductionism" - the process by which science breaks things down into their
basic parts, the better to understand them.
like E O Wilson, still proudly claim for science the capacity to describe
reality completely by reducing everything to its physical components
. Other scientists, particularly those aware of the
dynamics and problems of biological science, are increasingly less certain
of the Cartesian thesis.
To do him justice,
Descartes was not too well understood in respect to an analytical approach
to nature. Having advocated what later became reductionism, he went on to
propose that the whole nevertheless be built up from the parts "... as far
as the knowledge of the most complex..." through the same sort of chain of
reasoning used in geometry (at which he was expert).
The Cartesian model had one unfortunate result - which was to baffle
philosophers for 300 years. If the mind (soul) is an entity which somehow
resides in the physical body, exactly how does each relate to the other? In
1994, some 350 years after Descartes death, editors of a philosophical work
on consciousness could still write that
Even though everybody agrees that mind has something
to do with the brain, there is still no general agreement on the exact
nature of this relationship .
Following Ludwig Von Bertalanffy
 it is becoming increasingly plain that
reductionist thinking is woefully inadequate. Perhaps if Descartes had
lived today he would have advocated something similar to what is now
called General Systems Theory.
this states that what we know as reality, from the macro (the universe) to
the micro (fundamental particles), can be properly understood only in terms
of wholes. Knowing how the parts operate and interact gets us somewhere. The
only way to discover how constituent parts work is by the analytical
process. This is, to put it one way, knowledge about the world.
The whole is greater than the sum of the parts. Even if all the parts are
fully described and known, the whole means more. For example, you might
theoretically one day know your cousin in terms of every physical
constituent - from fundamental particles to minute-by-minute
electro-chemical functions of the brain.
you really understand your cousin if you know all these things?
Obviously not, for your cousin is a "person" - the holistic term we use for
describing one kind of biological system we call "human".
Systems theory was born in the twentieth century. Biologists like
Bertalanffy struggled to make sense of the way living entities operate in
their environments. How the "mind" is related to the "body" inevitably posed
a problem. Is it a "thing" which is a component of the overall physical
system? Or is it a "thing" somehow independent of the body?
The systems view of reality abandons mind as a "thing", either as part of or
as separate from the body. Instead it's thought of not as "mind" but as
"mental process". Mind isn't a thing but a particular aspect of the way
human systems work. The mind doesn't "know" something. Rather, humans go
through a process of knowing. Memory then fixes a remnant of thought
in a way we don't yet understand in detail.
the more viable systems theories is the Santiago Theory of Cognition. It
identifies the process of knowing with life itself. The mind is
... the activity involved in the self-generation and
self-perpetuation of living networks ... cognition is the very process
of life. The organizing activity of living systems, at all levels of
life, is mental activity ... Thus life and cognition are inseparably
connected. Mind - or, more accurately, mental activity - is immanent in
matter at all levels of life .
In other words, all living things in a sense are
mental processes. Systems such as humans have a structure, which can be
analysed. But they also have an ongoing process by which their structure
maintains and develops. Cognition (mind) is a critical part of that
organising activity which includes perception, emotion and behaviour.
"Mind" is process and "brain" is structure.
Another way of perceiving "mind" is to recognise that the word labels (but
does not describe) a particular aspect of a human being. For example, a
horse perceived exclusively from its rear end might seem singularly
unattractive. But perceived as a whole system, as a living, moving being it
Ervin Laszlo points out that science
attempts to explain mental phenomena "... in terms of neurophysiological
processes". That is, when we know how
mental processes operate we suppose we know what mind is.
This, says Laszlo, isn't wrong. It's just that it doesn't go far enough. It
is better, he says, to think of "mind" from at least two perspectives:
 The reductionist perspective which gives us a
vocabulary of "brain language" such as cell-assemblies, neural
interactions, sensory stimuli, intracortical activity and so on. This is
a labeling approach.
 Mind can also be
perceived as one's personal experience, including thoughts, beliefs
and one's overall experience of the world. The subjective experience
is integrated into a map or schema which represents both myself and
Each perspective represents an aspect of the system I
call "me". They are not different "things" but the same entity
perceived from different perspectives - that is, "mind" and "body" form a
... [two] sets of irreducibly different mental and
physical events [which] constitute an identical psychophysical system ..
What has for centuries been called "mind" is both the workings
of the brain and the subjective experience of those workings. Mind is the
same "thing" or process perceived in totally different ways.
of defining reality is, in my view, entirely new. It is, in effect, a
radically new paradigm which will eventually change the way we relate to the
world. Starting in the 1970s it has already given birth to a new stream of
endevour - cognitive science.
Although the life of pure
Cartesianism was short, it nevertheless greatly extended the duration of
modern dualistic perceptions of reality.
thoroughgoing philosopher, Descartes had to have a go at metaphysics. A
continuing question is how, if at all, we can know anything about God.
Descartes tried to prove God's existence - though quite how he could hope to
conclude anything about God (ultimate reality) if he wasn't sure that other
people exist, or that speech or writing or society or the universe are real,
boggles the mind.
One of his "proofs" (used before
in slightly different form by Thomas Aquinas) went something like this
- Whenever I have an idea of an object, whatever
characteristics I clearly and distinctly understand the object to have,
it really has;
- And I have a clear and distinct idea of God as
the maximally perfect being;
- God is perfect (literally, "has all perfections");
- Everlasting existence is perfection;
- God has everlasting existence;
- Therefore God exists.
This sort of propositional reasoning can obviously be
used to "prove" the existence of anything - a perfect person or a perfect
motor car. It also embodies false logic. It's logically valid to argue
that if it's true that Bush is the President of the USA, and if the
President exists, it follows that Bush exists. But it's obviously invalid
to argue that if Pegasus is a winged horse, and a winged horse exists in
the book Greek Myths, then winged horses exist.
So Descartes can say something like "In the idea of
God, God is perfect." But if he does so, then all he's actually saying is,
"If God exists, then God exists." And anyway, the argument hasn't proved
that a perfect God is possible, never mind that he, she or it exists. Nor
has it shown that everlasting existence is better than finite existence.
Overall, it seems to me, the Cartesian method fails to
establish that anything can be known. First, the device used to establish
the reality of "soul" is based on a type of reasoning which fails because
it fractures the whole. Once separated from "body", the "mind" cannot be
reunited with it. Nor can it be shown by what mechanism the mind knows
anything about itself.
And, second, if body and mind are separated one from the
other, then nothing "external" to mind can be the object of experiment
because the data yielded by experiment cannot be matched with the data
existing in the mind. The former is uncertain. The mind, being the only
real thing in the equation, can't rely on uncertain information.
In other words, the basis of all science and analytical
thought is demolished by both dualism and determinism. Since Cartesians
use analytical thought to arrive at their conclusions this turns out to be
an unfortunate consequence.
Cartesian Doubt was appropriate in, and congruent with,
the times in which it was born. But because the proof of the pudding is in
the eating, it's life as a credible school of thought was justifiably
Karen Armstrong suggests that the limitation of human
reason to rational thought is inherently limiting. For example, pure
rationality cannot answer the question, "Why do we exist?", though
it has much to tell us about how we exist. She writes:
Descartes beside his stove, in his cold, empty world,
locked into his own uncertainty, and uttering a "proof" which is little
more than a mental conundrum, embodies the spiritual dilemma of modern
Elsewhere she points out that the social effects of
Cartesianism were to have long lasting and somewhat unfortunate results
in that people
... were excited by the idea of a mechanical universe,
ruled at all times and in all places by the same unequivocal laws.
Increasingly the mechanical universe would be seen as a model for
society. Citizens should submit to a national government in the same way
as the different parts of the cosmos obeyed the rational laws of the
scientific God. 
That approach has been long-lived, perhaps because it
has reinforced an ancient and persistent way of regarding the world.
Dualism and determinism retain a firm place in the minds of many.
 History of Western Philosophy
 Consilience, 1998
 Consciousness in Philosophy and Cognitive Neuroscience,
Revonsuo et al
quoted by Fritjof Capra in The Hidden
 General System Theory, 1968
 Hidden Connections, Fritjof Capra
 Introduction to Systems Philosophy, E Laszlo, 1972
 From Early Modern Philosophical Theology by Derk Pereboom
A Companion to the Philosophy of
Religion, Eds P L Quinlan & C Taliaferro
 The Battle For God, HarperCollins, 2001
 The Case for God, The Bodley Head, 2009