[39] Apology, XVII.
[40] Against Celsus, II, 40.
[41] Treatise VI, § 9. See, also, Tertullian: Apology, XVII; "And this is the crowning guilt of men that they will not recognize One of whom they cannot possibly be ignorant."
[42] Against the Heathen, I. 33.
[43] Dialogue with Trypho, IV, "Even Homer distinguishes simple seeing (ἰδεῖν) from νοεῖν, which implies perception by the mind as consequent upon sight."
[44] Hortatory Address to the Greeks, V.
[45] Exhortation to the Heathen, XI.
[46] Stromata, IV, 25. In V, 12, he explains what he means by "demonstration": "Nor any more is He apprehended by the science of demonstration, for it depends on primary and better known principles. But there is nothing antecedent to the Unbegotten."
[47] "Against Celsus, VII, 20. See also VII, 44, and Clem. Alex.: Stromata, II, ii, 4, and often.
[48] E.g., Theophilus (I, 1, 2) replies to the demand: "Show me thy God," by the counter-demand: "Show me yourself, and I will show you my God."