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‪Our study concerns the cumulativeness and the diversification of the exports of countries. We try to understand whether the relationship between cumulativeness and diversification is stable or if it is, somehow, affected by the cognitive dimension of countries and products. Thus, in order to offer some possible answers, we have carried out estimations on countries with different levels of development. In addition, our study stands out by grasping the role of the cognitive component of products on the basis of a qualitative differentiation. Consequently, through this empirical work, we shall ask three questions: first of all, is the specialization in the different quality ranges cumulative? Next, we shall try to ascertain whether the relationship between cumulativeness and diversification is antagonistic, as shown by theoretical models; in other words, is the emergence of trade diversification likely to reduce the learning potential of countries? Finally, we shall ponder the question of whether vertical differentiation consolidates the statistical stylized facts that assert the existence of a positive relationship between the size of a country and its degree of diversification. Beyond the highlighted results, this paper opens up new avenues of research, especially concerning the implication of knowledge externalities in the evolution of comparative advantages within a cognitive economy.