DALIBOR JÍLEK – JANA MICHALIČKOVÁ CYIL 7 ȍ2016Ȏ makes uniform or autonomous interpretation easy. Its conceptual components are not tied with any legal system. Such a concept has not retained uniformity though. De Steiger attributed a slight uncertainty to the concept of habitual residence without trying to find its substance in connotations different from the 1961 Hague Convention. He diminished the attribute of uncertainty of the content exclusively in relation to protection of children. 80 He explained the content of the concept of habitual residence by means of a descriptive definition which observed the usage of this linguistic constituent. Habitual residence should have been the effective centre of the life of a child ( le centre effectif de la vie du mineur ). 81 Despite the fact that the Hague Conference produced new international conventions using the concept of habitual residence, none of them contained the definition. If a question of habitual residence is a matter of pure facts, then the explanation of the concept could seem to be useless. 82 Of course, any concept, either legal or factual, could be subject to definition. 3. The European Union Law: relation of ostensive and descriptive definition of habitual residence The law is a matter of language and its concepts are transferred from one form to another. 83 Regulation No 3/58 of the Council dated 25 September 1958 concerning social security for migrant workers introduced in Art. 1 (h) a binding definition of permanent residence. The definition explained the concept of permanent residence with the aim of prescribing the content and usage in the Community law: The ‘permanent residence’ means ‘the place where a person habitually resides’. The definition as a generalised unit comprises definiendum and definiens . The phrase of habitual residence does not appear on the right side in definiendum but on the left side in definiens . Any occurrence of the definiendum can be replaced by an occurrence of the definiens. And, conversely, any occurrence of the definiens can be replaced by an occurrence of the definiendum . 84 Obviously a simple definition places semantic equality between permanent and habitual residence. It is linguistically totally homogeneous. A definition includes similar, correlated words. However, 80 DE STEIGER, M. W. Rapport Explicatif. Actes et documents de la Neuvième session. Conferénce de la Haye De droit international privé, 1961, Tome IV, p. 234. See the 1961 Convention concerning the powers of authorities and the law applicable in respect of the protection of infants. 81 Ibid. 82 GRAVESON, R. H., NEWMAN, K. M. H., ANTON, A. E., and EDWARDS, D. M. The Eleventh Session of the Hague Conference of Private International La w. The International and Comparative Law Quarterly, 1969, Vol. 18, No. 3, pp. 620, 629. 83 KOSKENNIEMI, Martti . The Politics of International Law . Oxford and Oregon: Hart Publishing, 2011, p. 298. 84 GUPTA, Anil, ‚Definitions‘, The Stanford Encyclopedia of Philosophy (Summer 2015 Edition), ZALTA, Edward N. (ed.), URL = .