The fact that the Universe is, everywhere and always, in a permanent evolution, is a rather recent discovery. At the contrary, the origin of the Universe has been the theme of a debate ever since millenaries. Today, the debate has basically changed its nature, as it rests upon astronomical observations, non only, as it was since the old days, upon purely metaphysical considerations. On the one side, the invention of Einstein's Relativity, pushed the scientists toward building models of the Universe that observations of distant galaxies could help to substantiate. This confrontation led, in the years 1946-52 to the elaboration of the "big bang model", - a "standard" model - which developed later, successively inspired by the new observations that were piling up until today, as the "precision cosmological model". Such a model is generally accrpted. However, several objections have been enunciated, and alternative models have been suggested, not implying, unlike the big bang type models, any "initial instant" - a "creation", would say the philosophers. Those models ("stationary" or "quasi-stationary") account for obervations just as well as models that were derived from the big bang concept. The conclusion of the debate is still much out of reach. One thing at least is obvious: one cannot experiment on the Universe as can physicists on the physical laws. Only the weaknesses of one or another model of the Universe could be demonstrated. But it will never be possible to "prove" the validity of any model of the Universe, without being obliged to imply some hypothesis of a metaphysical nature.