Full Idea
When we expect it to be day tomorrow, we all behave as empiricists, because until now it has always happened thus. The astronomer alone knows this by reason.
Gist of Idea
We all expect the sun to rise tomorrow by experience, but astronomers expect it by reason
Source
Gottfried Leibniz (Monadology [1716], §28)
Book Reference
Leibniz,Gottfried: 'Philosophical Writings', ed/tr. Parkinson,G.H.R. [Dent 1973], p.183