[15] Aristotle, Met. v. 4.

[16] Aristotle, Met. xii. 2.

[17] Aristotle, Met. vii. 8.

[18] Aristotle, de Anima, ii. 5.

[19] Aristotle, Met. xii. 5.

[20] Aristotle, Met. ix. 8.

[21] Aristotle, Met. ix. 5.

[22] That is, their producing potentiality, and not the potentiality of becoming these things, as thought Aristotle. Met. ix. 2.

[23] As thought Aristotle, Soul, iii. 7; Met. xii.

[24] By Plato in the Timaeus 52.