Realism is a development of the Platonic theory of Forms which stated that universals such as "red" or "man" have an independent, objective existence, either in a realm of their own or in the mind of God. In modern philosophy, realism is a broader term, including several philosophical movements whose agreement rests in the common rejection of philosophical Idealism. In its most general form realism asserts that objects in the external world exist independently of what is thought about them. This philosophy of realism stresses an important core of truth that cannot help but expand an individual's search for understanding and truth.
In the same way, the metaphysical realist takes the world and its non-intentional, or non-mental, aspects and parts to exist as is and to have total, fully-completed natures regardless of anything having peculiarly to do with cognition. Albert Einstein once asked his friend Abrahm Pais if he really believed that the moon existed only if he looked at it. Einstein himself had no doubts as to the answer. In his view the commonsense belief is correct. The moon does exist in objective reality whether or not anyone is observing it (Bradley, 1979)
Thus, if you go on a realist field trip to an apple orchard, you will see trees loaded with round red, green and yellow apples. The apple trees do vary in some aspects, but all are similar as members of the same class. As trees, they share in the form of what is an apple tree. There is the general category, botanical reality, and the particular trees that are members of the class. Take several apples home with you. Taste their different flavors, look at their colors, shape and form. Open them up and see the star that greets you. These trees and their qualities existed before you came on this trip and will exist after you leave.
Philosophical rationalism includes several forms of thought that share the belief that reality is rational in nature and that making the necessary deductions is essential to gaining knowledge. Deductive logic and mathematical processes are the main methodological tools. Rationalism accepts the view that there are no ultimate answers, but knowledge is nevertheless possible. Truth is a continuous search.
The best example of the philosophy was by Descartes. Starting with the reality of doubt, he determined to accept nothing of which he could not be certain. Yet one reality could be deduced from this: He was doubting and must therefore exist. In his words, "I think, therefore I am." Rationalism is a thus a philosophy that relies on reason and logic as the basis for testing any claims of truth, searching for objective knowledge about reality, forming judgments and conclusions. Rationalism must eventually rely on sense perceptions, but it must also use these with logic and evidence. Scientific method is derived from rationalism and based on the premise that there is no concrete or final truth, and all conclusions about reality are always tentative, subject to continual revision from additional evidence.
A rationalist field trip would be to go back in time and join Gottfried Wilhem Leibniz in considering a thought experiment.
Let us assume that some individual should instantly become the King of China, with the further constraint that he would lose all memory concerning his former life just as if he would be born anew. Wouldn't that -- practically speaking -- be indistinguishable from the situation in which the individual would be destroyed and a King of China brought into being at the same moment and the same place? The individual has no reason to wish for that (Mates, 1986).
Pragmatism sees reality as a process or experience. Knowledge is gained in trial-and-error, and values are set by norms of society that seeks the greatest happiness for the greatest number over the long-term. Pragmatism was founded by Charles S. Peirce in 1872. His "Illustrations of the Logic of Science" constitute an description and defense of the method of science -- or of any empirical or experimental method of inquiry. Peirce argues that this is the method…