This article discusses the problem of selecting the extralinguistic invariant content of texts for the effective teaching of translation of scientific and technical literature. The texts of various scientific disciplines which consider the diverse spectrum of different objects can be formed into groups. These groups of texts, in which only one aspect of an object is taken into account, are referred to as metathemes. The authors propose the general criterion of selecting extralinguistic content of the texts based in a metatheme approach. The full list of forty aspects or metathemes for various scientific disciplines is described and the procedure of selecting texts is discussed. As an example the results of an analysis of the texts in engineering are summarized as a distribution of the texts in terms of metathemes. The article also demonstrates the way in which a common semantic organization of a specific metatheme can predict the linguistic content.