Letter XVI FROM the antagonism of the two impulsions, and from the association of two opposite principles, we have seen beauty to result,...

Letter XV I APPROACH continually nearer to the end to which I lead you, by a path offering few attractions. Be pleased to follow me a...

Letter XIV WE have been brought to the idea of such a correlation between the two impulsions that the action of the one establishes and...

Letter XI If abstraction rises to as great an elevation as possible, it arrives at two primary ideas, before which it is obliged to stop...