p One of the most widespread methods of scientific cognition, especially in natural science, is scientific observation, a purposeful contemplation and perception of objects and phenomena in their natural state, i.e., such as they are in reality. The results of observation depend on the extent of the researcher’s preliminary knowledge of the object which he studies, on his ability correctly to formulate the purpose of his investigation and his determination to achieve his aim, and his skill to give a faithful and exhaustive description of the results obtained.

p As distinct from observation, an experiment is investigation of an object that is placed in artificial, carefully considered conditions. This makes it possible to fix and study the object in its pure form and to ascertain how the object as a whole and its individual aspects change under the influence of specific conditions. For example, having obtained one or another chemical substance in its pure form, a chemist studies its properties and finds-out how they change under the influence of temperature, humidity, pressure and other factors.

Experiment is one of the most important methods of cognition. It is broadly employed in natural science and is steadily gaining in importance in social sciences. There are all kinds of experiments ranging from small laboratory tests to vast production ones. Today, when science is becoming a direct productive force, production is turning into a huge experimental field where scientific discoveries, new machines and technology, and new scientific methods of the organisation of labour and management are put to severe and all-round tests.