Why is there something instead of nothing?

“…now we…make use of the great…principle that nothing takes place without a sufficient reason; in other words, that nothing occurs for which it would be impossible for someone who has enough knowledge of things to give a reason adequate to determine why the thing is as it is and not otherwise. This principle having been stated, the first question which we have a right to ask will be, ‘Why is there something rather than nothing?’…. Further, assuming that things must exist, it must be possible to give a reason why they should exist as they do and not otherwise. “Now this sufficient reason for the existence of the universe cannot be found in the series of contingent things….Although the present motion…arises from preceding motion, and that in turn from motion which preceded it, we do not get further however far we may go, for the same question always remains. The sufficient reason, therefore, which needs not further reason, must be outside of this series of contingent things and is found in a substance which…is a necessary being bearing the reason for its existence within itself; otherwise we should not yet have a sufficient reason with which to stop. This final reason for things is called God.”

- Leibniz (1714)