The assumed distinction between causation as natural and super-natural no doubt began in superstition in prehistoric time, and throughout the historical period has continued from a vague feeling that the action of God must be mysterious, and hence that the province of religion must be within the super-sensuous. Now, it is true enough that the finite cannot comprehend the infinite, and hence the feeling in question is logically sound. But under the influence of this feeling, men have always committed the fallacy of concluding that if a phenomenon has been explained in terms of natural causation, it has thereby been explained in toto—forgetting that it has only been explained up to the point where such causation is concerned, and that the real question of ultimate causation has merely been thus postponed. And assuredly beyond this point there is an infinitude of mystery sufficient to satisfy the most exacting mystic. For even Herbert Spencer allows that in ultimate analysis all natural causation is inexplicable.
Logically regarded the advance of science, far from having weakened religion, has immeasurably strengthened it. For it has proved the uniformity of natural causation. The so-called natural sphere has increased at the expense of the 'super-natural.' Unquestionably. But although to lower grades of culture this always seems a fact inimical to religion, we may now perceive it is quite the reverse, since it merely goes to abolish the primitive or uncultured distinction in question.
It is indeed most extraordinary how long this distinction has held sway, or how it is the ablest men of all generations have quietly assumed that when once we know the natural causation of any phenomenon, we therefore know all about it—or, as it were, have removed it from the sphere of mystery altogether, when, in point of fact, we have only merged it in a much greater mystery than ever.
But the answer to our astonishment how this distinction has managed to survive so long lies in the extraordinary effect of custom, which here seems to slay reason altogether; and the more a man busies himself with natural causes (e.g. in scientific research) the greater does this slavery to custom become, till at last he seems positively unable to perceive the real state of the case—regarding any rational thinking thereon as chimerical, so that the term 'meta-physical,' even in its etymological sense as super-sensuous or beyond physical causation, becomes a term of rational reproach. Obviously such a man has written himself down, if not an ass, at all events a creature wholly incapable of rationally treating any of the highest problems presented either by nature or by man.
On any logical theory of Theism there can be no such distinction between 'natural' and 'supernatural' as is usually drawn, since on that theory all causation is but the action of the Divine Will. And if we draw any distinction between such action as 'immediate' or 'mediate,' we can only mean this as valid in relation to mankind—i.e. in relation to our experience. For, obviously, it would be wholly incompatible with pure agnosticism to suppose that we are capable of drawing any such distinction in relation to the Divine activity itself. Even apart from the theory of Theism, pure agnosticism must take it that the real distinction is not between natural and supernatural, but between the explicable and the inexplicable—meaning by those terms that which is and that which is not accountable by such causes as fall within the range of human observation. Or, in other words, the distinction is really between the observable and the unobservable causal processes of the universe.
Although science is essentially engaged in explaining, her work is necessarily confined to the sphere of natural causation; beyond that sphere (i.e. the sensuous) she can explain nothing. In other words, even if she were able to explain the natural causation of everything, she would be unable to assign the ultimate raison d'être of anything.
It is not my intention to write an essay on the nature of causality, or even to attempt a survey of the sundry theories which have been propounded on this subject by philosophers. Indeed, to attempt this would be little less than to write a history of philosophy itself. Nevertheless it is necessary for my purpose to make a few remarks touching the main branches of thought upon the matter[50].
The remarkable nature of the facts. These are remarkable, since they are common to all human experience. Everything that happens has a cause. The same happening has always the same cause—or the same consequent the same antecedent. It is only familiarity with this great fact that prevents universal wonder at it, for, notwithstanding all the theories upon it, no one has ever really shown why it is so. That the same causes always produce the same effects is a proposition which expresses a fundamental fact of our knowledge, but the knowledge of this fact is purely empirical; we can show no reason why it should be a fact. Doubtless, if it were not a fact, there could be no so-called 'Order of Nature,' and consequently no science, no philosophy, or perhaps (if the irregularity were sufficiently frequent) no possibility of human experience. But although this is easy enough to show, it in no wise tends to show why the same causes should always produce the same effects.
So manifest is it that our knowledge of the fact in question is only empirical, that some of our ablest thinkers, such as Hume and Mill, have failed to perceive even so much as the intellectual necessity of looking beyond our empirical knowledge of the fact to gain any explanation of the fact itself. Therefore they give to the world the wholly vacuous, or merely tautological theory of causation—viz. that of constancy of sequence within human observation[51].
If it be said of my argument touching causality, that it is naturalizing or materializing the super-natural or spiritual (as most orthodox persons will feel), my reply is that deeper thought will show it to be at least as susceptible of the opposite view—viz. that it is subsuming the natural into the super-natural, or spiritualizing the material: and a pure agnostic, least of all, should have anything to say as against either of these alternative points of view. Or we may state the matter thus: in as far as pure reason can have anything to say in the matter, she ought to incline towards the view of my doctrine spiritualizing the material, because it is pretty certain that we could know nothing about natural causation—even so much as its existence—but for our own volitions.