J. B. Pratt's 1922 version of the AFR

Let us continue a little farther the line of thought suggested by the materialist s denial of efficiency to consciousness. Since consciousness never interferes with physical processes, never affects them in any way, the whole of man s civilization, the sum total of his achievements, both material and spiritual, must be ascribed to purely physical laws. The whole tre mendous mass of it through all the ages would have come about just the same if no scientist or inventor had ever had a thought, no poet or artist a sentiment, no moral or religious teacher an aspiration or ideal, no patriot a feeling of loyalty, no mother an emotion of love. But leaving these things on one side, let us consider in more detail one aspect of the denial of the efficiency of consciousness which should be of par ticular interest to our materialistic friend. Conscious ness, he will remind us, is always an effect and never a cause. And this means, if Materialism is to be self- consistent, that every psychic state, every feeling and every thought, is determined in its totality by the correlated brain process and never in any degree by any preceding psychic state. To say that a thought is even in a minute degree a co-cause of the follow ing thought would be to wreck Materialism. In the process known as reasoning, therefore, it is a mistake to suppose that consciousness of logical relations has anything whatever to do with the result. It is not logical necessity but mechanical necessity that squeezes out our so-called reasoned conclusions. Take the familiar syllogism: All men are mortal. Socrates is a man. . . Socrates is mortal. The materialist assures us that we should be falling back into the primitive superstitions of a pre-natural- istic age should we suppose that either of the pre mises had anything to do with our arriving at the conclusion. We finally assert that Socrates is mortal not because we have in mind the mortality of all men and the humanity of Socrates, nor for any other logical or psychological reason; but because certain mechanical processes in our brains force that thought into consciousness. Thus no conclusion is ever ar rived at because of logical necessity. There is no logical necessity among mental processes but only physical necessity. The truth is, according to Ma terialism, we think the way we have to think, the way our mechanical brains constrain us to think. We may happen to think logically; but if we do, this is not because logic had anything to do with our con clusion, but because the brain molecules shake down, so to speak, in a lucky fashion. It is plain, therefore, that no conclusion that we men can reach can ever claim to be based on logic. It is forever impossible to demonstrate that any thesis is logically necessary. If we happen to entertain it we do, that is all; for demonstration is out of the question. This seems plainly to be the inevitable outcome of the materialist doctrine. And it gives an interesting and somewhat surprising turn to the discussion. For suppose at this point we ask the materialist why he maintains that Materialism is true. If he hopes to convince us he can only reply that he considers Materialism true because it is the logical conclusion from certain admitted facts, or that the falseness of all other theories can be logically demonstrated. . . . The hopeless self-contradiction of such a position is obvious. With one breath the materialist asserts that his doctrine is logically demonstrable and that there is no such thing as logical demonstration. As Brad ley has put it, no theory can be true which is inconsistent with the possibility of our knowing it to be true.