Dr Chalmers attached high value to the distinction between the ethics of theology and the objects of theology, and expatiated with great eloquence on the duty which is laid upon men by the probability or even the imagination of a God (Nat. Theol., B. i. ch. i. ii.) "Man is not to blame, if an atheist, because of the want of proof. But he is to blame, if an atheist, because he has shut his eyes. He is not to blame that the evidence for a God has not been seen by him, if no such evidence there were within the field of his observation. But he is to blame if the evidence have not been seen, because he turned away his attention from it. That the question of a God may be unresolved in his mind, all he has to do is to refuse a hearing to the question. He may abide without the conviction of a God, if he so choose. But this his choice is matter of condemnation. To resist God after that He is known, is criminality towards Him; but to be satisfied that He should remain unknown, is like criminality towards Him. There is a moral perversity of spirit with him who is willing, in the midst of many objects of gratification, that there should not be one object of gratitude. It is thus that, even in the ignorance of God, there may be a responsibility towards God. The Discerner of the heart sees whether, for the blessings innumerable wherewith he has strewed the path of every man, He be treated like the unknown benefactor who was diligently sought, or like the unknown benefactor who was never cared for. In respect at least of desire after God, the same distinction of character may be observed between one man and another--whether God be wrapt in mystery, or stand forth in full development to our world. Even though a mantle of deepest obscurity lay over the question of His existence, this would not efface the distinction between the piety on the one hand which laboured and aspired after Him, and the impiety upon the other which never missed the evidence that it did not care for, and so grovelled in the midst of its own sensuality and selfishness. The eye of a heavenly witness is upon all these varieties; and thus, whether it be darkness or whether it be dislike which hath caused a people to be ignorant of God, there is with Him a clear principle of judgment that He can extend even to the outfields of atheism."--(Pp. 72, 73.) The Rev. Alexander Leitch, in the First Part of his 'Ethics of Theism' (1868), discusses in a thoughtful and suggestive manner the following subjects: the reality and universality of the antithesis between truth and error, the legitimate dependence in all cases of belief on knowledge, the responsibility of man for his whole system of belief, the distinction between mystery and contradiction, the distinction between speculative and practical knowledge, the distinction between certainty and probability, the standard of morality, and the claims of reason and faith.