Litterally « the Great Art of Knowledge or Combinatorics », Athanasius Kircher's Ars Magna Sciendi sive Combinatoriae (1669) d’deals with philosophy and, more precisely, logic. In this treatise, we discover a daring work, which takes upArs Magna by the Spanish Franciscan theologian Ramon Llull (1232-1315).

Kircher's table retracing Llull's Great Art is divided into nine lines designated by nine letters of the alphabet and seven rows: questions, absolute principle, relative principle, subject, virtue, vice. The table is then transferred to a wheel divided into nine sections. On three concentric circles, we find the letters, the absolute and concrete principles, connected to each other by a line.

In the 13th century, Ramon Llull was one of the forerunners of combinatorial dialectics. After an epiphany around the age of thirty, Llull decided to design an art form, bearing universal validity and based on the divien attributes ((goodness, infinity, eternity, etc.). Llull's Great Art is the study of the combinations of the fundamental principles of each sciences by means of embedded circles. The rotation of these circles allows a large number of possible combinations, each of which leads to a conceptual "truth".

An aid to reasoning, the logical machine invented by Ramon Llull fits in the missionary objective of establishing the truth of Christian dogma by demonstrating the need for the Trinity from premises shared by all three monotheist religions.

Between the mid-16th and mid-17th centuries, the idea of an art of memory and thinking that unfolds in a « mechanical » way is revived. The « mechanism », as we call « the innovations that characterize the mutation of rationality conceptually and practically », marks, in the history of science, the beginning of modernity. As a modern man, Athanasius Kircher was convinced of the role that machines must play in the progress of science and education. Mechanics occupies a central position in his thinking, as shown by his many schemes and inventions. As a baroque man, Athanasius was looking for innovation, novelty, but also for the curious, even the fantastic or the esoteric.

PConvinced that the first experts in mechanical technology were the Egyptians, the dream of universal knowledge would always push him to study, explore and invent. In his Ars Magna Sciendi sive Combinatoriae, Athanasius Kircher shares the idea that prompted Ramon Llull to work on combinatorial analysis : clavis universalis, i.e. an universal language that should be decrypted in order to reach the original truth. Thus, about three centuries later, the Jesuit was inspired by the work of the Franciscan by carrying out his own study, aimed at the creation of logical machines. Starting from the principle that it is possible to relate all scientific truths, Kircher makes Llull's system more mathematical and more complex in order to design machines which, according to the laws of logic, make it possible to reach conclusions that are not only valid but also, according to Kircher, true.