XIX. Philosophical Maxims. Morals. Polemics and Speculations: 1211.

1211.

On spirits (1211--1213).O mathematicians shed light on this error.

The spirit has no voice, because where there is a voice there is a body, and where there is a body space is occupied, and this prevents the eye from seeing what is placed behind that space; hence the surrounding air is filled by the body, that is by its image.