Cartesianism

Cartesianism represents the ideas of the 17th century French philosopher and mathematician Rene Descartes. It has been called "the father of modern philosophy" due to it's innovative methodological doubt. A form of Rationalism, Cartesianism upholds a Metaphysical Dualism of two finite substances, mind and matter, called Mind-Body Dualism.

The Cartesian methodology in philosophy is based on doubt in everything. Descartes doubted in sensory experience, existence of external world and even his own body. Through radical skepticism he was led to only one thing that can be certain - thought processes.

Descartes brought the question of how reliable knowledge may be obtained (epistemology) to the fore of philosophical enquiry. Many consider this to be Descartes' most lasting influence on the history of philosophy.

Cartesianism is a form of Rationalism because it holds that scientific knowledge can be derived a priori from 'innate ideas' through deductive reasoning. Thus Cartesianism is opposed to both Aristotelianism and Empiricism, with their emphasis on sensory experience as the source of all knowledge of the world.

For Descartes, the faculty of deductive reason is supplied by God and may therefore be trusted because God would not deceive us.

Descartes argued that humans often cannot distinguish between real life and dreams, suggesting that our senses are unreliable sources of knowledge. This analogy reinforced his claim that knowledge must be rational, not perceptional.

According to the Cartesian method, the only thing we can be certain of is the existence of our own thoughts, meaning the existence of the individual as a thinking being is the only certainty. Even if a malevolent supernatural being, referred to as deus deceptor, were deceiving us into doubting everything—our senses, the existence of the external world, our physical bodies, and even basic mathematical or logical truths—the one thing we can still be sure of is that we exist as thinking beings. The phrase "Cogito ergo sum", meaning "I think, therefore I am," expresses that the very act of thinking proves our existence.

Descartes distinguished the mind and the body in metaphysical manner, that is called mind-body dualism. He believed that mind (or soul) is thinking, immaterial substance, whose essence is thought itself, and the body is non-thinking, material substance. This claim led to mind-body problem, that later philosophers attempted to explain.

According to Descartes, mind can be equated with soul as it is believed in many religions - it is immortal, incorporeal, has free will and can exist beyond matter.

Descartes explained interactions of mind and body through the pineal gland in the brain, which would be center of mental activity located inside human body.

Descartes held that all existence consists in three distinct substances, each with its own essence:

• Matter, possessing extension in three dimensions.
• Mind, possessing self-conscious thought.
• God, possessing necessary existence.

Descartes tried to prove the existence of God, who is believed to give certainty of reality being real. He described two arguments:

• Trademark Argument: The idea of perfection, infinity and absolute cannot be just invented by finite and limited being like human. Thus the very idea of infinity and absolute perfection must be implanted by higher being.
• Ontological Argument: The very concept of God defined as absolute perfection must exist, because existence is the first necessary quality of perfect being.

Main article: Mechanism

According to Descartes, entire universe and all living beings operate on deterministic laws of nature. He rejected Aristotelian teleology, and supported an idea that everything is composed of matter and motion and functions accordingly to physics and mathematics, not on neither purpose nor mystical life force.

As a substance dualist, he argued that reality is composed of two radically different types of substance: extended matter, on the one hand, and immaterial mind, on the other. He identified matter with the spatial extension which is its only clear and distinct idea, and consequently denied the existence of vacuum. The only thing that is separate from mechanistic, deterministic laws of physics is conscious mind. Descartes' dualism was motivated by the seeming impossibility that mechanical dynamics could yield mental experiences.

Descartes made an extremely important contribution to mathematics by developing analytic geometry, which connects algebra with geometry.

He introduced cartesian plane, a system where points in space are described by numerical coordinates ((x, y) in 2D space, (x, y, z) in 3D space). It left possibility to show geometric shapes as algebraic equation, leaving way to development of calculus.

Contrary to theory in Aristotelian physics, Descartes developed law of inertia, which later influenced Newtonian laws. It states that objects remain in their state (motion or rest) unless acted upon by an external force.

Before Newtonian laws of gravity, Descartes proposed a model where planets are carried by cosmic vortices caused by subtle matter in space (such as aether).

Sun is the greatest object in the solar system, so the vortex created by sun is most powerful one, holding all other celestial objects. Planets have their vortexes, therefore moons are orbiting them.

This theory was later disproven by Isaac Newton.

Descartes believed that body works literally like a machine. For example, the heart functions as a pump, circulating blood based on pressure, and nerves operate through a fluid-based system reminding hydraulic technologies.

Descartes believed that animals are entities incapable of thinking and feeling, composed only of body and primordial instincts, working mechanically, thus they can be treated by humans, which are capable of thought, whatever they want.

Related philosophies: Hobbesianism, Nietzscheanism, Non-Self, Spinozism

Critics mainly discuss Descrates' metaphysical or ethical arguements.

1. Draw a ball
2. Color it pink
3. Draw a four pane window
4. Fill it with yellow
5. Draw a green tree in each square
6. Add the two eyes

You are done!

• Skepticism - A good method, everyone should use it at least once in their life.
• Platonism - The first rationalist.
• Stoicism - I can see why they were the happiest of men.
• Virtue Ethics - I haven't built a strong enough metaphysical system to start really doing ethics yet, but this is basically what I believe in.

• Aristotelianism - Great for his time, but your teleological conceptions of nature can only lead to confusion.
• Positivism - I appreciate your devotion to science, but you need to realize that knowledge can only come from reason.
• Solipsism - After a long period of consideration, I have come to the conclusion other people do in fact, exist.
• Catholicism - I am a loyal member of the Catholic Church. Please don't censor me!

• Scholasticism - Nothing personal, but you've got it all wrong.
• Hobbesianism - A dangerous idiot.
• Materialism - Material cannot be the first principle, they are finite substances and can be doubted without performative contradiction.
• Nietzscheanism - Denies the notion of self among with many other things.
• Psychoanalysis - What is this Id and Superego talk? I especially hate Lacan.
• Animal Ethics - These meaty things feel nothing, I will demonstrate you *takes a knife and put it in dog's guts*

• Cartesianism