"One of the things that made his Zettelkasten or slip box (or note card file) so intriguing to the larger (German) public was a 1981 paper, entitled "Kommunikation mit Zettelkästen. Ein Erfahrungsbericht" (Communication with Index Card Systems. An Empirical Account. [...]) Luhmann claimed that his file was something of a collaborator in his work, a largely independent partner in his research and writing. It might have started out as a mere apprentice when Luhmann was still studying himself (in 1951), but after thirty years of having been fed information by the human collaborator it had acquired the ability of surprising him again an again. Since the ability of genuinely surprising one another is an essential characteristic of genuine communication, he argued that there was actually communication going on between himself and his partner in theory.
Luhmann also described his system as his secondary memory (Zweitgedächtnis), alter ego, or his reading memory or (Lesegedächtnis)."
Learning and memory are by default automatic processes; their efficacy is proportional to the relevance that the thing to be learned has to your life (frequency, neurons firing together, synaptic pruning, interconnections, etc.). You could say that this relevance acts as filter for incoming information.
There are reasons why you might want to sneak information past this filter ("artificial learning"):
To learn abstract knowledge that is far removed from daily life (e.g. math). This is done using analogies, mnemonics, examples, anthropomorphism, etc.
To interfere with the process of "natural learning" with the goal of improving learning mechanisms, for example when learning a skill like playing the piano. This is done using deliberate practice, analysis, etc.
See these methods as gardening techniques. We either let the garden of the mind grow naturally or we sculpt it deliberately.