The given article investigates the role and function of metaphors used to present new scientific knowledge which is being illustrated by heuristic scientific texts in English. History of developing different conceptions of metaphors is presented herewith. The science of heuristic is rich with abstract concepts, which are possible to describe only by metaphors. Metaphors are based on analogy. Analogy helps to apply an object or event of one class to quite a different class of objects or events by finding a similarity between them. A human being realizes the unknown by associating it with the known, that is with objects or events of the surrounding physical world. The investigation in this paper is performed with the help of a conceptual analysis, which analyzes the meaning of a word and conceptions associated with that meaning. The language used in heuristic scientific texts to describe mental activity is meta-language which is based on “common sense”.