Cosmology and celestial mechanics

The similarities between cosmology and celestial mechanics are discussed from the scientific and historical points of view and the scientific aims of these two fields are compared. Newton's and Poincaré's contributions to celestial mechanics, dynamics, and cosmology are presented. The recently established instability of triple stellar configurations is discussed to relate results of this classical, nonintegrable problem of celestial mechanics to cosmology and to offer an example for order out of chaos. It is shown that the presently emphasized reasons for limited predictability in dynamical systems are closely related to some of the existing basic difficulties in cosmology.