1137.
Weight, force and casual impulse, together with resistance, are the four external powers in which all the visible actions of mortals have their being and their end.
1138.
Our body is dependant on heaven and heaven on the Spirit.
1139.
The motive power is the cause of all life.
Psychology (1140-1147).
1140.
And you, O Man, who will discern in this work of mine the wonderful works of Nature, if you think it would be a criminal thing to destroy it, reflect how much more criminal it is to take the life of a man; and if this, his external form, appears to thee marvellously constructed, remember that it is nothing as compared with the soul that dwells in that structure; for that indeed, be it what it may, is a thing divine. Leave it then to dwell in His work at His good will and pleasure, and let not your rage or malice destroy a life—for indeed, he who does not value it, does not himself deserve it [Footnote 19: In MS. II 15a is the note: chi no stima la vita, non la merita.].
[Footnote: This text is on the back of the drawings reproduced on Pl. CVII. Compare No. 798, 35 note on p. 111: Compare also No. 837 and 838.]