On the basis of their individual preliminary studies, the authors consider in this article the impact of Darwinism on psycho-pedagogical constructs in Belgium in the period before the Second World War. Their findings are put together around three positions, which are, in fact, hypotheses for further research: (1) The "influence" of Darwin on Belgian psycho-pedagogical theory did not proceed in a straight line but generally indirectly, that is, via the mediation of other, foreign authors, such as, for example, Herbert Spencer and Ernst Haeckel; (2) The ideological fault lines between Catholics and non-Catholics--in particular between Catholics and atheists or free-thinkers--were drawn very clearly in the Belgian reception of Darwin, also with regard to the formation of psycho-pedagogical constructs. In general, however, the Catholics did not condemn Darwinism as such--indeed, they often developed their own Catholic evolutionism--but they were very unwilling to expand the principle of evolution to include the human or social sciences. Many were of the opinion that this would imply a denial of the "soul"; (3) The central figure in the historical process of "associating" with the theory of evolution was that of "appropriation" in which diverse elements of evolutionism were taken out of their historical context and were "functionalistically" inserted into an alien environment. (Contains 46 footnotes.)