Abstract Since the second half of 18th century, new instruments produced many data and improvements (not only in mechanics) of the scientific knowledge and its applications. Thanks to Euler and Lagrange, the differential equations started to become an important instrument to solve very complex problems, beforehand considered as unsolvable. The Traité de mécanique céleste (1805) by Laplace represents the climax of such an approach and soon becomes part of an important process of exaltation of ..
