p Knowledge is the reflection of reality in man’s consciousness, the conscious reproduction ot the object under study, its properties and relations, in the form of ideal images.

p Idealist philosophers oppose the proposition that knowledge (cognition) is the reflection of reality. Thus, subjective idealists reduce it to the study of the relationship between sensations and notions, regarding them as the basis of all being. On the other hand, objective idealists present knowledge as the self-development of the idea (the mind), irrespective of the material world. The German philosopher Gottfried Wilhelm Leibnitz, for instance, wrote: “Our thoughts come from our own Self without any direct influence of all other creatures on the Soul.”  [133•1 

p Though exponents of the above concept recognise that the world is cognisable, they divorce knowledge from reality, from its practical transformation, and thereby in fact hamper the attainment of true knowledge.

p As distinct from philosophers who recognise the knowability of the surrounding world, but distort the essence of cognition, agnostics (a is the Greek for “no”, and gnosis for knowledge) reject any possibility of cognising the outside world. Agnostic views were held by Immanuel Kant, David Hume, and others. Hume, for instance, reasoned that only images or sense-perceptions were within the reach of our mind. We do not know the source or causes of these images. They may result from the influence of objects on our sense organs, or from the energy of the mind itself, or from the action of some invisible and unknown spirit, or from something else. Experience, he continued, should have told us all about this, but at this point it is silent and cannot be otherwise, since the mind, having to do only with sense-perceptions, is unable to compare sense-perceptions with the object. In this case, any experience will be reduced to a comparison of some sense-perception with others.

p Hume’s proposition that experience attests to the unknowability of objective reality is absolutely unfounded. Experience, if treated materialistically as the practical activities of men, shows, on the contrary, that man is capable of cognising the outside world and that knowledge is the reflection of objective reality in man’s consciousness in the form of ideal images.

p This reflection, however, is neither passive nor mechanical. It is a constructive and creative activity. The subject does not reflect everything he sees, but only that which is necessary for his 135 vital activities, which is connected in some way with his requirements and can be used to satisfy them.

In cognising reality, people set themselves particular objectives that determine the range of objects chosen for study, the main avenues of knowledge, its forms, and so on. The content of these objectives is determined by the level of the development of society, particularly that of the productive forces and the corresponding relations of production among people, as well as by that of knowledge itself. Today, for instance, man sets himself such objectives as to learn the laws governing the interaction of the “elementary” particles that go to make up the nucleus of an atom, to study the structure of the molecules that underlie the vital processes in an organism and to understand the mechanics of storing and retrieving information. In the not-so-distant past, however, his goals in natural science were confined to pinpointing the chemical and physical properties of substances (revealed through their interaction), describing and classifying living organisms.