11 clarify the meaning and scope of a given conventional provision, it is an interpretative declaration, while if one intends to modify a given conventional provision or to exclude its application, it is a reservation. In practice, it is not always easy to draw the dividing line between one and the other 35, as illustrated by the controversy which has surrounded, in the last decades, the question of the legal effects of declarations inserted into the instruments of acceptance of the optional clause of compulsory jurisdiction, given the sui generis character of such clause. 31. In any way, in considering the meaning and scope of a declaration of acceptance of an optional clause of compulsory jurisdiction, - such as the one presented by Trinidad and Tobago under Article 62 of the American Convention and interposed as preliminary objection in the present case Constantine, - one has to bear in mind the nature of the treaty in which that clause appears. This corresponds to the "context", precisely the second component element of the general rule of interpretation of treaties set forth in Article 31 of the two Vienna Conventions on the Law of Treaties. In the present Judgment, the Court has duly done so, in stressing the special character of the human rights treaties (pars. 94-97). 32. Likewise, the Court has kept constantly in mind the third component element of that general rule of interpretation, namely, the "object and purpose" of the treaty at issue, the American Convention on Human Rights (pars. 82-83 and 88). Thus, the understanding advanced in the cas d'espèce by the respondent State of the scope of its own acceptance of the optional clause of compulsory jurisdiction of the Inter-American Court, does not resist the proper interpretation of Article 62 of the American Convention, developed in the light of the canons of interpretation of the law of treaties. 33. As I saw it fit to point out in my Separate Opinion in the case Blake versus Guatemala (Reparations, 1999), "(...) In contracting conventional obligations of protection, it is not reasonable, on the part of the State, to assume a discretion so unduly broad and conditioning of the extent itself of such obligations, which would militate against the integrity of the treaty. The principles and methods of interpretation of human rights treaties, developed in the case-law of conventional organs of protection, can much assist and foster this necessary evolution. Thus, in so far as human rights treaties are concerned, one is to bear always in mind the objective character of the obligations enshrined therein, the autonomous meaning (in relation to the domestic law of the States) of the terms of such treaties, the collective guarantee underlying them, the wide scope of the obligations of protection and the restrictive interpretation of permissible restrictions. These elements converge in sustaining the integrity of human rights treaties, in seeking the fulfillment of their object and purpose, and, accordingly, in establishing limits to State voluntarism. From all this one can detect a new vision of the relations between public power and the human being, which is summed up, ultimately, in the recognition that the State exists for the human being, and not vice-versa. The juridical concepts and categories, inasmuch as they enshrine values, are a product of their time, and, as such, are in constant evolution. The protection of the human being in any circumstances, against all the manifestations of arbitrary power, corresponds 35 . It may be recalled that in the well-known case of Belilos versus Switzerland (1988), the European Court of Human Rights considered that a declaration interposed by Switzerland amounted to a reservation - of a general character - to the European Convention on Human Rights, incompatible with the object and purpose of this latter. European Court of Human Rights, Belilos versus Switzerland case, Judgment of 29.04.1988, Series A, n. 132, pp. 20-28, pars. 38-60.