Tracing across eras from the age of the Platonists the notion of plenitude in a (rather!) academic study.
It began with the Platonic explanation of the universe having so many manifestly imperfect things: what was perfect was the universe, and its perfection consisted of having every possible type of being.
Onward through its mutations. The philosophers who debated whether God had created freely. The philosophers who insisted, as soon as the notion of other worlds like ours arose, that obviously they had to be inhabited. The philosophers who rejected the notion of progress because it would require that the plenitude not be complete at some point.
