According to Geary's evolutionary approach, humans are able to easily acquire primary knowledge and, with more efforts, secondary knowledge. The present study investigates how primary knowledge contents can facilitate the learning of formal logical rules i.e. secondary knowledge. Framing formal logical problems in evolutionary salient contexts should increase learners' efficiency, motivation and engagement in learning compared with framing logical problems in secondary knowledge. In two experiments, high school students (n=210) had to train with syllogisms of unknown content (to reduce the use of prior knowledge) and which could be related to primary knowledge (rules about invented food and animals) or secondary knowledge (fictitious mathematics and grammar rules) in order to best pass a final test. The training phase was compulsory or left to learners' choice. In a third experiment, participants (university students, n=227) were confronted with three phases: (i) a priming phase consisting of problems with primary or secondary knowledge contents, then (ii) a training phase consisting of secondary knowledge only and (iii) the final test. Results confirmed the positive influence of primary knowledge in a learning task: participants were more efficient, more motivated, more confident and experienced less cognitive load when confronted with primary knowledge compared to secondary knowledge. In particular, primary knowledge favored the involvement and persistence of learners in the training phase regardless of their personal characteristics unlike secondary knowledge. Finally, presenting primary knowledge first and then secondary knowledge was more efficient both in terms of performance and motivation. The evolutionary approach to knowledge would provide a framework for developing a way to present new content that is cost-efficient in keeping learners motivated, whatever their age or personal characteristics.