The Six Books of Proclus on the Theology of Plato, Volume 2

For if it is converted to itself, but every thing which is converted to itself is self-subsistent, the soul also is self-subsistent, and produces itself. But it is likewise life and vital, and its hyparxis is according to vitality. For it imparts life by its very being to the natures to which it is present. And if the participant is adapted, it immediately becomes animated and vital, [soul in effecting this not reasoning][308] nor acting from deliberate choice, nor vivifying by cogitation and judgment, but by its very essence, and by that which it is, supplying the participant with life. Hence the being of soul is the same as to live. If therefore the soul possesses being from itself, and this is the same as to live, and it has life essentially;—if this be the case, it will impart life to itself, and will possess it from itself. And this being admitted, soul will be self-vital.