Abstract

The question whether the universe has existed for an infinite or only a finite time, along with the question whether a causal series might go back infinitely far into the past, has loomed large in attempts to prove the existence of God. These questions, together with that of the extent of the future, are now discussed. They lead us to consider the principle of sufficient reason and to ask whether there can be any ultimate explanations, whether the regress of explanations can ever be brought to a satisfactory end.