Rationalism and empiricism are two main approaches in the epistemology. Rationalism is a philosophical direction that recognizes the intellect as the basis of knowledge and human behavior. The first teachings of the rationalism can be found in Plato’s works. The ancient philosopher neglected sensuous cognition as it can not provide people with verity. Perceptual knowledge was believed to prevent the proper use of human reason. Plato assumed the existence of innate ideas in the individual’s mind, which are not related to the experience. In this case, the philosopher actively opposed the materialism by stating that there is nothing but the illusion of cognition in it. The concept was defined as the source of human cognition, which has no form and exists separately.
In the Modern era, Rene Descartes proceeded to develop main ideas of the rationalism. It was stated that the human mind has the content that is objective and does not depend on the experience, which can be used in everyday life but is uncertain in the scientific activity. Rationalism assumes the existence of the verity, and there is the single way to achieve it. Every person has the same reason but people think differently because everyone has a different experience and peculiar sense perception.
This approach offers deduction as the experimental method of scientific knowledge, which means the movement from general concepts to single ones by deducing consequences from premises. Initially, there is a veritable knowledge in everyone’s mind which is in the axiom form and requires no proofs for its existence. People need to organize their experience in accordance with these axioms, which indicates that knowledge is enjoined to the world and subordinated to the inner knowledge, instead of being its reflection. Rationalists notice that most of the world’s theories are obtained as a result of enlightenment and intuition but not intensive experimental researches. Descartes defined it as an intellectual intuition which helps to organize the reliable knowledge on the basis of the perceptible world’s diversity.
Rationalism states that all human knowledge can be verified by the cleaning power of doubt. The science must start with the positions, which do not depend on the experience and senses of people. Methodical doubt is the way to exclude all statements that can not be prerequisites for a deductive philosophical system. In this case, Descartes claimed: “I think, therefore, I am” (Newman, 2010). This philosophical principle rejected the significance of the experience because interaction between nature and the human spirit was considered to be impossible. It was also implied that doubt must destruct the traditional culture and become the ground for the rationalist culture. This approach raises the question of the cognition reliability which must be the original premise and, therefore, can not rely on other premises.
Cognition issues are closely related to the specific method to achieve the most veritable and reliable knowledge. Basing on the concept of perfection, Descartes inferred on the perfect being existence which can be considered as a proof for God’s existence. The verity criterion appears to be rationalistic and indicates that sense perception must be under control of the human reason.
Contrary to rationalism, empiricism is an approach that recognizes the perceptual experience as a source of knowledge and asserts that all knowledge is based on the experience. The first concepts of empiricism can be found in Aristotle’s early works. The eminent philosopher was the first to identify the experience as the set of memories about the definite subject. It was stated that the experience is a result of sensory perception and its accumulation in the memory. The level of experience along with sensory perception prevents people from making mistakes and brings the individual knowledge. Aristotle’s empiricism is holistic as it always refers to the speculation.
As the epistemological conception, empiricism appeared in the XVII-XVIII centuries. John Locke is considered to be one of the most outstanding representatives of this approach. At this time, the main attention was paid to the cognition problems. It was stated that the study of human cognition’ abilities and their limits is the prerequisite for many researches. Empiricists noticed that the intelligence, apart from the experience, can not bring a benefit. The most valuable knowledge is the one that benefits the mankind by improving people’s life conditions. In this case, Locke admits, "There is nothing in the mind that was not first in the senses" (Younkins, n.d.). It means that any human knowledge comes from the experience as people are not born with the background information in their minds. The mind receives information mediated by the senses only, which helps to create the definitive idea on the subject.
Empiricism also claims that the human mind is devoid of any innate ideas, concepts, or principles. The mind appears to be the blank sheet (or tabula rasa) and only experience, through the sensory perception, allows to fill it with knowledge. Except the external experience, there is the internal one (or reflection) which is the mind’s observation on its activity and ways of its manifestation. In its essence, the role of the human reason is limited by simple empirical judgments. Contemplation is supposed to provide two main types of ideas for the human mind: simple and complex. Simple ideas are provided by one of the human senses only (e.g. the ideas of warmth, light). Complex ideas are the result of comparison, observation, and connection of simple ideas.
Thus, rationalism is based on the idea that human reason is the main tool of the cognition. Knowledge is a reflection of the actual world which exists regardless the human being. On the other hand, empiricism claims that human senses are the source of the veritable knowledge. In this case, the content of knowledge can be represented as a description of the experience. Rene Descartes and Jock Locke determined the main concepts of the epistemology and founded a new methodology of scientific knowledge, which had a great influence on the future philosophical ideas.