HOW DO WE KNOW WHAT IS REAL Philosophy

HOW DO WE KNOW WHAT IS REAL? Philosophy Meetup

THE FIELDS OF PHILOSOPHY �Metaphysics – the study of the nature of reality. �Epistemology – the study of the nature of knowledge �Axiology – the study of the nature of value. § Ethics –values in the realm of morality § Aesthetics– values in the realm of beauty and art �Logic – principles of right reasoning

METAPHYSICS The study of the nature of reality

METAPHYSICAL QUESTIONS �What is reality? �Why is there something and nothing? �What is a being? �What is a person? �Am I free? �Is there a supreme being?

METAPHYSICAL QUESTIONS �Who am I? �Why am I here? �Where did I come from? �Where am I going?

DEFINITIONS v Metaphysics: the philosophy of being which seeks to answer questions about existence. v Metaphysics: study of questions about the world left unanswered by the natural sciences, such as those regarding First Causes; Laws of the Universe; Mind/Body; Freedom/Determinism. v First used by Aristotle who wrote first his Physics (concerning the physical world) and the Metaphysics (beyond the physical world).

2 FOUNDATIONAL PRINCIPLES � � Principle of non-contradiction - no real being can both be and not be at the same time and in the same respect. Principle of sufficient reason: every being has the sufficient reason for existence in itself or in another. It is not possible for something to be its own cause (otherwise it would violate the Principle of non-contradiction). Every being that does not possess the sufficient reason for its own existence in itself must have an efficient cause (necessarily extrinsic to itself).

THEORIES �Common Sense Realism § What people perceive under ordinary conditions is reality.

THEORIES �Idealism § George Berkeley 18 th Century § Denies existence of material things § Reality is ideas and the minds that hold these ideas § “Esse est percipi” (“to be is to be perceived”) § Objects are ideas that God placed in humans

THEORIES v Platonic Realism • Reality is ideal forms or ideas that are timeless, unchanging, immaterial, and more perfect than the world of changeable things • Forms in the World of Being _____________ • Things in the World of Becoming

THEORIES �Materialism or Physicalism § Pre-Socratic Philosophers § Everything is physical; Reality consists of matter. § Matter – particles in motion and forces like gravity.

THEORIES �Monism § Reality is one all encompassing thing § All particular things are expressions of this one thing § Things can be material or mental § Baruch Spinoza argued it could also be divine § String Theory – everything is composed of one-dimensional strings of energy Materialism and Idealism are Monist Theories

THEORIES �Dualism § Descartes § Reality consists of two things: Mind and Matter § Interactionism is a common version of dualism § Mind and Body co-exist as separate entities

MATERIALISM VERSUS DUALISM Materialism § Man is simply an animal, and brains are simply chemical systems § No soul § Humans are like computers. Dualism § Mental is separate from Physical § Mind and Soul can preexist the body and survive bodily death § Dualists believe in the afterlife, and the paranormal

DISCUSSION QUESTIONS v What do you think is really real? v What is ultimate reality? v Why is there something rather than nothing? v Are you a materialist or a dualist? v Where did we come from? v Why are we here? v Where are we going? v Do we have a mind distinct from the body? Or is the mind simply brain states? v Are we free?

EPISTEMOLOGICAL QUESTIONS �What is the proper definition of truth? § Options: § Correspondence § Coherence § Pragmatism § Truth should be defined as that which corresponds to reality. �What is knowledge? § Properly justified true belief. �Is truth absolute or is it relative? § Are there some things that are true objectively? �What can we know? Can we know the answers to life’s greatest questions?

EPISTEMOLOGICAL QUESTIONS �What are legitimate sources of truth? § Options: § Experience § Reason § Revelation (authority) § General Revelation § Special Revelation

RATIONALISM �The Rationalism of Plato § Knowledge is possible because it is innate. § Fundamental ideas or principles are built right into the mind itself and require only to be developed and brought to maturity.

THE RATIONALISM OF DESCARTES �How Descartes found Certain Knowledge § § He doubted everything doubtable. in order to find one thing that was undoubtable. He would build his knowledge upon this one undoubtable thing. The one undoubtable thing: He was a thinking substance. § “I doubt; therefore I think. ” § “I think; therefore I am. ”

EMPIRICISM �What is Empiricism? § Empiricism—the view that all knowledge is derived from sense experience.

JOHN LOCKE’S EMPIRICISM § The mind is a tabula rasa (“blank tablet”) before the input of experience. �Locke’s epistemological dualism: The two factors involved in knowledge are (1) mind which knows, and (2) its ideas which are known. § The ego-centric predicament: If we know only our ideas directly, how can we be certain of their correspondence with things in the external world?

RADICAL EMPIRICISM -- HUME �David Hume: The source of all knowledge is perceptions. �All ideas are derived from impressions – vivid or lively sensations.

Radical Empiricism -- Hume �Though we have a natural belief in self and causality (every event must have a cause), experience gives us no rational knowledge of either of these; therefore we must be skeptical of their reality. �Hume’s position is known as phenomenalism: All we can actually know is the phenomena or appearances presented in our perceptions.

SKEPTICISM �Varieties of Skepticism § Common-sense skepticism: healthy incredulity about unlikely or preposterous claims. § Philosophical skepticism: doubt about cherished philosophical ideas. § Absolute skepticism: the denial of knowledge itself.

VIDEO CLIPS ON REALITY �The Matrix - What is Real? �What is Reality? �How To Tell if You Are Dreaming

ALL POSSIBLE KNOWLEDGE

DREAMING �How do you know that you are not dreaming? �How To Tell if You Are Dreaming