Introduction

Philosophy is the science of estimating values. The superiority of any state or substance over another is determined by philosophy. By assigning primary importance to what remains when all secondary elements have been removed, philosophy becomes the true index of priority or emphasis in the realm of speculative thought. The mission of philosophy a priori original: "a priori." A Latin term referring to knowledge that comes from theoretical deduction or self-evident causes rather than from observation or experience. is to establish the relationship between manifested things and their invisible ultimate cause or nature.

"Philosophy," writes Sir William Hamilton A 19th-century Scottish philosopher known for his work in metaphysics and logic., "has been defined as: The science of things divine and human, and of the causes in which they are contained [Cicero]; The science of effects by their causes [Hobbes]; The science of sufficient reasons [Leibniz]; The science of things possible, inasmuch as they are possible [Wolf]; The science of things evidently deduced from first principles [Descartes]; The science of truths, both sensible and abstract [de Condillac]; The application of reason to its legitimate objects [Tennemann]; The science of the relations of all knowledge to the necessary ends of human reason [Kant]; The science of the original form of the ego The "I" or the self-aware part of the mind. or mental self [Krug]; The science of sciences [Fichte]; The science of the absolute [von Schelling]; The science of the absolute indifference of the ideal and real [von Schelling]—or, the identity of identity and non-identity [Hegel]." (See Lectures on Metaphysics and Logic.)

The six headings under which the disciplines of philosophy are commonly classified are:

• Metaphysics, which deals with abstract subjects such as cosmology The study of the origin and development of the universe., theology, and the nature of being;
• Logic, which deals with the laws governing rational thinking—or, as it has been called, "the doctrine of fallacies";
• Ethics, which is the science of morality, individual responsibility, and character, concerned chiefly with an effort to determine the nature of good;
• Psychology, which is devoted to the investigation and classification of those forms of phenomena originating in the mind;
• Epistemology, which is the science concerned primarily with the nature of knowledge itself and the question of whether knowledge may exist in an absolute form;
• Aesthetics, which is the science of the nature of and the reactions awakened by the beautiful, the harmonious, the elegant, and the noble.

Plato regarded philosophy as the greatest good ever granted by Divinity to humanity. In the twentieth...