Idealization is one of basic issues in the epistemology of sciences. According to its standard explanation by means of so called idealization conditions it applies to a strongly limited range of language terms. Contrary to this „local conception“ a „global“ one is developed in the paper, according to which idealization is a constitutive part of the language of science as such, and not only of some of its terms. The idealization of motion is explained in terms of Husserl’s analysis of Galileian revolution, which gave birth to the language of physics. The pattern is then applied to the explanation of Pythagorean revolution. Attention is paid to the explanation of how the idealization of shape made the language of mathematics possible.