Aristotle’s Theory of Knowledge

The philosophical idea of ancient Greece reached the greatest height in Aristotle’s works. Aristotle’s views, which encyclopedically incorporated achievements of ancient science, are a grandiose system of specific and scientific and actually philosophical knowledge in its surprising depth, subtlety, and scale. Aristotle was not the author of the theory of knowledge (Plato was); however, he was the one who gave it that form in which it exists today. Nowadays, Aristotle’s theory of knowledge plays an important role for philosophy and the perception of science in general. Thus, Aristotle’s theory of knowledge has to be studied in more detail in order to estimate its interrelation with science.

Cognitive activity is studied by a special area of philosophy, which is known as the theory of knowledge, or gnoseology (from ancient Greek “gnosis” – knowledge). The theory of knowledge has already appeared in ancient philosophy. Socrates taught that original knowledge needs to be distinguished from the view that knowledge is expressed in concepts. Plato considered that the truth is the comprehension of the eternal and invariable ideas. Aristotle constructed the complete doctrine about knowledge and developed logic as a science about forms of the correct thinking. Knowledge is a product of cognition and a result of active interaction between the subject and object.

Cognition is an active reflection and perception of reality in consciousness of a person. Cognition represents the movement from ignorance to knowledge as well as from incomplete and inexact knowledge to fuller and exact one. In the course of cognition, various informative abilities of the person are used. People learn many things during the usual life and practical activities, but they also create a special form of cognitive activity, namely a science, the main goal of which consists in the achievement of reliable and objective, i.e. true knowledge. For this purpose, in science, various methods of knowledge are used, namely supervision and experiment, induction and deduction, promotion of hypotheses and creation of theories.

From Aristotle’s point of view, cognition passes a way from the person’s perception of external subjects to knowledge. The philosopher divided consciousness into sensual and intelligent. At a stage of sensory perception, feelings play a major role. According to Aristotle, feelings are a passive (derivative from external) state, and they cannot exist without external influence. The feeling is a prerequisite to cognition; thus, the beings having feelings will learn nothing and understand nothing.

The difference between the feelings and knowledge is dictated by the fact that feelings occur from the outside and reflect the separate and single phenomena. Knowledge deals with general and exists to some extent in the soul.[1] Therefore, everyone can think when necessary while the feeling does not depend on the human will; in fact, it requires the presence of the subject exciting this feeling. The first and initial step of intelligent cognition is an opinion, which comprises at the same time both conclusion and belief. The opinion is comprehended by means of experience and is formed on the basis of judgment; thus, the opinion is an empirical method of knowledge. The opinion can be a delusion, and it can extend over the area of sensual and subject to change facts.

Intelligent knowledge exists in the form of definitions and proofs. Unlike perception, the subject of knowledge is something general and necessary but not single and casual. Unlike the opinion, knowledge in the form of judgment is always true and leads to understanding of bases (reasons) of existence of a thing. Aristotle recognized the unity of sensory and reasonable perception, according to which, feeling and knowledge are basically the same ability of the soul. The soul does not consist of subjects; for example, there is not a stone in it but a form (an image) of a stone. Therefore, the subject of thought is also reflected in sensually comprehended forms, including so-called abstractions, which makes properties and states of something sensually felt.

Aristotle’s doctrine about active and passive mind deserves a specific attention. The active mind is similar to the light allocating potentially existing colors. It thinks through the prism of concepts and comprehends the truth. On the contrary, the passive mind occurs when a person addresses to mental subjects. In the passive mind, there are truth and lie, and it is a form of existence of the active mind.

Aristotle was one of the first to offer the classification of cognitive processes on the basis of the definition of functions and properties of the soul. Except feelings, the soul includes memory, imagination, and thinking. Aristotle’s doctrine had an impact on the development of psychology of cognitive processes up to the present day. For example, he proved a hypothesis, which in many centuries has been issued in the form of the law of associations and the associative memory concept, and he also formulated the laws of thinking proved by means of logically derived scientific concepts.

In the theory of knowledge (as well as in a number of questions of physiophilosophy and mathematics), Aristotle closely approached materialism, protecting (unlike Plato) the origin of knowledge out of feelings. Though Aristotle hesitated between dialectics and metaphysics, his philosophies are considerably peculiar elements of dialectic understanding of reality. Aristotle investigated the most essential forms of dialectic thinking. [2]Criticizing the Eleatic denial of the movement, Aristotle called them as “not devotees” and “anti-naturalists”. He considered that ignorance of the movement necessarily involves ignorance of the nature. Elements of dialectics were brightly shown in Aristotle’s statement of the question of the relationship between the possibility and reality, form and content, and others.[3]

Aristotle built his theory of knowledge believing strongly in the concept of logic. The philosopher claimed that the possibility of faults makes human minds determine the accuracy of the truth of a given claim. In other words, he supposed that the intellect has adequate reasons that may insure that the offered judgments correspond to reality. Thus, according to Aristotle, such reasons are likely to be the base of perfect knowledge, i.e. perfect knowledge is achieved through the causes.