Dualism

The two primary and opposing beliefs are that of dualism, the idea that the mind and body are separate entities, and physicalism, the idea that mind and body belong to the same physical entity.

Materialism is the doctrine that the world is entirely physical, whereas dualism is the doctrine that there are two fundamentally different kinds of things in the world: mind and bodies. Dualists say that minds are not made out of physical stuff, and they are not subject to the laws of nature.

Physicalism is a form of ontological monism—a "one substance" view of the nature of reality as opposed to a "two-substance" (dualism) or "many-substance" (pluralism) view.

Physicalists do not refute that humans think and feel. However, they refute the claim by dualists that the mind occurs as a non-physical entity. They maintain that these thoughts and perceptions by a human being are species of physical facts rather than immaterial sensations.

epiphenominalism

Descarte before the horse

Rene Descartes' Six Meditations is part of Descartes explanation on how his method of doubt will allow him to temporarily cease to believe all the things that he cannot know for certain, and finally executes the first part of that plan. He goes through the basic principles which underly his beliefs, doubts those basic principles, and then wipes clean all of his previous beliefs.

The book is made up of six meditations, in which Descartes first discards all belief in things that are not absolutely certain, and then tries to establish what can be known for sure. He wrote the meditations as if he had meditated for six days: each meditation refers to the last one as "yesterday".

On the basis of clear and distinct innate ideas, Descartes then establishes that each mind is a mental substance and each body a part of one material substance. The mind or soul is immortal, because it is unextended and cannot be broken into parts, as can extended bodies.

Meditation I introduces his method of doubt or methodological skepticism. He feels that the best way to reach clear and distinct knowledge is to begin by doubting the evidence of his senses that there exists an external world including other people and his own body. He has torn down all his beliefs because of his dream skepticism, or the possibility that he is dreaming, and that there is the possibility that he is being deceived by an evil genius or malicious demon.

Meditations II he sets out to determine whether there is anything that he could be certain of after the doubts of Meditations I. He quickly determined that there is: the fact that I exist. But to know that I exist is one thing, and to know exactly what I am is something else.

Meditations III explores the existence of God, Who has been defined as the "existing one" or the "unmoved mover" or the "cause of creation". All that exists has a cause because of Cause and effect is fundamental for something to exist. If I exist, and I am not merely an idea, something must exist that caused me or caused the things that caused me. So, therefore I am not alone. Observing the order of the universe we see a God as the cause or creator takes less faith than a Big Bang. (see The Return of the God Hypothesis: The mind behind the universes, Stephen Meyer)

• (1) The essence of God must be a perfect being because he "cannot conceive of God as not being a perfect being".
• (2) Existence is a perfection. (consistent patterns in nature.)
• (3) Therefore, God exists.

Meditations IV God cannot be a deceiver since he does not participate in any way in nothingness. People, on the other hand, are finite beings, and that their lack of infinite being implies that they also participate in nothingness(things that do not exist like lies and darkness, or false imaginings or opinions).

Meditation V examines the Essence of Material Things and also raises the questions about the order and relation between the two main arguments for the existence of God introduced in Meditation III and the ontological argument it presented.

Meditation VI "The existence of material things, and the real distinction between mind and body," seeks to demonstrate that the external world of physical things exists and that the mind and body are independent substances, capable of existing without the other, hence dualism.