The authoress ponders on a topical and a controversial dilemma – whether and to what extent quantitative criteria of evaluation can be applied to science components. These components are considered to be both subjective and objective, e.g. scientists, scientific associations, institutions, publications, etc. All of them are submitted to opinions and estimation. The objective methods have been searched for a long time, and the controversy over their rightness continues. They are divided into two basic groups: peer review and numerical. The first is also called qualitative, the other quantitative. This differentiation may suggest that the quantitative methods do not comply with the quality criteria. Another important issue is the relation between scientific production quality and its quantity. The subject is very broad. For comprehensive discussion it would be necessary to present all methods and techniques applied, to draw comparisons, mention examples of their use, and results obtained.