[Not enough is known about solid geometry] and for two reasons: in the first place, no government places value on it; this leads to a lack of energy in the pursuit of it, and it is difficult. In the second place, students cannot learn it unless they have a teacher. But then a teacher can hardly be found.
Every heart sings a song, incomplete, until another heart whispers back. Those who wish to sing always find a song. At the touch of a lover, everyone becomes a poet.
To the rulers of the state then, if to any, it belongs of right to use falsehood, to deceive either enemies or their own citizens, for the good of the state: and no one else may meddle with this privilege.