The synthesis is involved here is not a simple mix of knowledge provided by different branches of science. It aims to highlight, comparing knowledge of different sources, gaps and contradictions of the dominant system of values.
Individual problems often come from the system more errors than individual mistakes. To be fertile, a synthesis should not be content to strengthen, somewhat by selfing, the existing system of thought, then it would only reinforce the prejudices and stereotypes that confine minds in ambient paradigms.
Instead it should highlight the errors of the system as much as those of individuals, in order to change these paradigms, while developing individuals.