as a cause,--if the farther progress of patient and unprejudiced inquiry showed that another, by the occurrence of instances in which it preceded the effect while the former did not, had a preferable title to be termed the cause, the mind in its unbiassed estimate of numbers at once admitted the claim. But when, according to the antagonist system,[82:1] it became settled that any given phenomenon had in it the power of bringing into existence another, that power was viewed as a quality of the object. When things are admitted to have qualities, it is not easy for the mind at once to assent to their non-existence and to admit that others have the proper title to these qualities. Analogy, the great source of fallacies, comes to increase the difficulty, by a confusion of what are termed the qualities of bodies, and those endowments with which we invest our fellow-creatures. In this respect Hume's theory of cause and effect has been of great service to inductive philosophy. It was an objection to it that it made no allowance for unseen causes; but it was part of its author's system, that the uniformity which our observation teaches us, proceeds unseen in those cases to which our observation cannot penetrate. It was part of the theory, that where there is a want of the absolute uniformity in the sequence of two phenomena, they are not respectively cause and effect. This principle is of vital importance in physical science. It is a notion with the vulgar, and one that sometimes perhaps lurks unseen in scientific operations, that the cause sometimes does not produce its effect by reason of some failure in the operating power. It is from a vague amplification of this heresy, that the popular notion of chance is derived. Hume's theory nips the bud of such a fallacy by denying, whenever there is a break in the sequence, that the phenomena which have in other instances followed each other, really are cause and effect. It is perhaps in the unscientific application of therapeutics, that the popular fallacy is most widely and most dangerously exemplified. The whole of the complexity of that wondrous science consists in the immediate causes and effects being unseen--in the phenomena immediately conjoined not being ascertained, but in attempts being made to estimate them through the connexion between those external causes to which the internal causes may have had the relation of effects, and those external effects of which these internal effects may have been the causes. The character of unseen causes was aptly illustrated by Hume himself, from the throwing of a die. The vulgar mind can see no cause and effect in the operation, because there is a series of causes and effects, which are hidden from the sight, in the interior of the box; but the philosopher knows not the less, that those laws of motion, which induction has established to him as truths, are taking place; and that there is no turn made by the die,