The art of flying is hardly yet born. It will be perfected and some day people will fly up to the moon. Do we pretend to have discovered everything, or to have brought our knowledge to a point where nothing can be added to it? Oh, for mercy’s sake, let us agree that there is still something left for the ages to come!

Bernard le Bovier de Fontenelle quoted by Emanuel Swedenborg in 1714. See: Flying Machine (Swedenborg) in Wikipedia.