Philosophy - Some Definitions
Philosophy is the "love and pursuit of wisdom by intellectual means and moral self-discipline." (American Heritage Dictionary)
Said differently, philosophy is "the investigation of the nature, causes, or principles of reality, knowledge, or values, based on logical reasoning rather than empirical methods." (Dictionary.com)
Epistemology is "the branch of philosophy that studies the nature of knowledge, its presuppositions and foundations, and its extent and validity." (Dictionary.com)
Posed differently, "What is the philosophical theory of knowledge?"
Philosophy - Some Modern Worldview Approaches
Different worldviews maintain different foundations of philosophy, based on different theories of knowledge. For instance, the Jewish, Christian, and Islamic views of philosophy agree in many particulars because all three belief systems are theistic, affirming the supernatural and miracles. Judaism, Christianity, and Islam also use faith and reason to support their religious beliefs.
In the last century, a major attack against Christian philosophy has been that its foundation is "unscientific." However, the Christian worldview claims that the doctrines of God, creation, Logos, design, purpose, law, morality, order, and life are reasonable, and consistent with the findings of science, history, and personal experience.
Secular philosophy is grounded in naturalism (or materialism). Naturalism is the philosophical belief that reality is composed solely of matter and that all phenomena can be explained in terms of natural causes (e.g., law of gravity). Therefore, the foundation of secular philosophy is its rejection of the supernatural. Secular philosophy's denial of the supernatural and reliance on science as its source of knowledge necessitates specific conclusions about our mortality, our mind, and the very nature of our humanity.
Like the secular view of philosophy, Marxist philosophy holds that the matter we see in nature is all that exists. This materialistic interpretation of the world is an essential ingredient of Marxist thought. The dialectic says that in everything there is a thesis (the way things are) and an antithesis (an opposition to the way things are), which will ultimately clash. The result of the clash is the synthesis, which becomes the new thesis. This new thesis will eventually attract another antithesis, and produce a new synthesis. For Marxists, this notion of dialectical materialism is the foundation of evolving, philosophical thought.
Philosophy - Some Postmodern Worldview Approaches
While there is no single cohesive Postmodern philosophy, a few consistent themes emerge from Postmodern scholars. One of the themes is a denial of universal, objective truth. Also, Postmodernists view the language of written texts through the goggles of "deconstruction," which means reading to discover subjective, hidden, or multiple meanings. In this way, a reader's interpretation of the text becomes more important than the text itself. Just as you are creating a personal meaning for this article, you also construct the world according to your culture and experiences. In other words, there is no "real world" out there, only billions of constructions of the world.
New Age philosophy is grounded in a contemporary view of Eastern thought systems, such as Hinduism, Buddhism, and Taoism, and in the Romantic poets of the 1800s, such as Ralph Waldo Emerson, Walt Whitman, and Henry David Thoreau. As such, New Agers reject naturalism and seek a transcendent, spiritual quality through personal meditation and reflection. New Age philosophy rejects the secular and Marxist positions, because such thought systems deny the supernatural and metaphysical. Since New Agers believe God is in everything, and everything is a part of God, they must conclude that everything, in essence, is spiritual. This view leads the New Ager to believe all matter can be controlled by an enlightened mind, and success, health, and love are ultimately the result of "mind over matter."
Philosophy - Conclusion
Contrary to popular belief, faith is critical in every philosophy. Therefore, when developing a foundation for our own philosophy, we must be extremely careful to base our position on the most reasonable, logical, and truthful assumptions. Again, contrary to popular teaching, the theistic philosophies require no more faith than the naturalistic philosophies. Indeed, we could argue that it takes a great deal more faith to believe in the spontaneous generation of life and the randomness of all nature than it does to accept the theistic doctrines of Creator and creation. The foundation of your philosophy is the key to your entire worldview. In the end, you must choose between supernaturalism (someone is responsible for all that we see) or naturalism (all that we see is responsible for itself). Your choice will dictate your philosophical presuppositions across every area of your life.