to their _causes_; on the other, that the inquiry into 'causes' is altogether vain and futile, and that Science has no concern but with the discovery of 'laws.' Which of these is the truth? Or are both views of the matter true _on a different interpretation of the terms_? Whichever view we may take, or whichever interpretation we may adopt, there is one thing certain,--the extreme inconvenience of such a state of language. This can only be reformed by a careful analysis of the widest of all human generalizations, disentangling from one another the innumerable shades of meaning which have got confounded together in its progress, and establishing among them a rational classification and nomenclature.... A 'law' may be a _rule of action_, but it is not _action_. The great First Agent may lay down a rule of action for himself, and that rule may become known to man by observation of its uniformity; but, constituted as our minds are, and having that conscious knowledge of _causation_ which is forced upon us by the reality of the distinction between _intending_ a thing, and _doing_ it, we can never substitute the 'rule' for the 'act.'"[191] But while the existence of "natural laws" and the operation of "second causes" are equally admitted, and yet duly discriminated, large room is still left for diversities of opinion or of statement in regard to _the precise relation which God sustains to His works_, and especially in regard to _the nature and method of His agency in connection with the use of "second causes_." Hence have arisen the various theories which have appeared successively in the history of Philosophy, and which have had for their avowed object the explanation of the _connection between God and Nature_, or the conciliation of Theology with Science.[192] Hence, first of all, the theory of "occasional causes," as taught by Father Malebranche, with the laudable, but, as we think, mistaken, design of vindicating the Divine agency in Providence by virtually superseding every other power in Nature;--a theory which represents physical agencies as the mere _occasions_, and God as the sole _cause_ of all changes, which teaches that a healthy eye, with the presence of light, is not the cause of vision, but the occasion only of that Divine interposition by which alone we are enabled to see, and that a man's desire or volition to walk is not the cause of his walking, but the occasion merely of that Divine interposition which alone puts the proper muscles in motion. Hence, secondly, the theory of "preestablished harmony" as taught by Leibnitz;--a theory which was mainly designed to explain the relation subsisting between the soul and the body, but which involves principles bearing on the general doctrine of cause and effect, and applicable to the relation subsisting between God and His works. This theory teaches that mind and body, although closely united, have no real influence on each other, that each of them acts by its own