agreeing in some circumstances, but differing in others, and all attended with the same result, a philosopher connects, as a general law of nature, the event with its physical cause, he is said to proceed according to the method of induction. This, at least, appears to me to be the idea which, in general, Bacon himself annexes to the phrase; although I will not venture to affirm that he has always employed it with uniform precision. I acknowledge also that it is often used by very accurate writers, to denote the whole of that system of rules of which the process just mentioned forms the most essential and characteristical part.'

It appears then, from the authorities I have cited, that there are at least three different modes of employing the term; viz. to denote,

1. The investigation of facts, preparatory to the formation of a general law;

2. The mere inferring of the general law from the facts brought together by such investigation; 3. The two preceding processes combined.

The first of these acceptations appears to me to be the most conformable to the general usage of philosophical writers, and for that reason the most convenient to adopt.

If this discussion should appear to turn on a mere question of phraseology, it must still be allowed, that to settle the meaning of so important a word

* Elements, vol. ii. p. 348.

as Induction is exceedingly desirable and worth some pains. At present it may be doubted whether any two men of science, taken at random and not being technical logicians, would give the same definition of it.

My principal aim, however, in the present chapter has been, in consonance with the subject of my treatise, to point out how far reasoning is concerned in this important combination of intellectual operations. I have accordingly endeavoured to show, that induction cannot be carried on without a continual intermixture of inferences with observation; and that the result to which the whole converges, is the formation of a general law, -itself an act of contingent reasoning.

CHAP. XI.

RULES FOR GUIDING THE OPERATIONS OF REASONING, AND ESPECIALLY THE RULES OF THE SCHOLASTIC LOGIC.

A TRUE theory of the reasoning processes, or, in other words, a thorough comprehension of their character, although fortunately not essential to the right performance of the acts, may be expected to assist us in some degree to arrive at correct conclusions; but will perhaps be more especially serviceable in preventing that misdirection of our powers, and that waste of attention on wrong objects, which are the usual results of a false theory on an important subject.

It must also tend to inspire us with confidence in our deductions, and with fearlessness in submitting them to the examination of others, in proportion as it enables us to discern the character of every link in the chain of argumentation.

Whether, nevertheless, such an insight into the nature of the processes will afford any formal rules to guide us in the performance of them, and whether any such rules are needed, seem to be points not equally clear.

From the preceding exposition of the subject, it

will have been seen, that the operations which pass under the name of reasoning are of a simple character; so simple, indeed, that a thorough comprehension of what they are seems all that is requisite to guard us against any irregularity to which they may be liable, if they are liable to any.

But this is a question which will perhaps be best elucidated by a separate examination of it in relation to each species of reasoning.

SECTION I.

Rules in Contingent Reasoning.

IN regard to those acts of contingent reasoning from one individual event to another, which are constantly occurring in the common business of life, rules can scarcely have place, since in them we do nothing but infer that some unknown event will happen, or has happened, in certain circumstances, from our having known a similar event to have taken place in similar circumstances: if any precept is wanted to guard us from mistakes, it is merely an injunction to take care that our premises are correct, i. e. that the circumstances are similar. We may erroneously regard cases as resembling each other, which really do not; a fault of observation, or a misconception, or a misrecollection, rather than an error of inference.

When, however, we turn to those important acts of contingent reasoning which consist in the in

ference of general laws, the case is somewhat altered in its aspect, and the operation seems less simple. Yet still it will be found, if I mistake not, that the greater complexity which then appears is the complexity of the several operations concerned in the preliminary inquiry needful to collect and arrange the facts from which the inference is to be drawn.

Accordingly, if we examine the rules which have been laid down by Lord Bacon and his followers, we shall find that they are precepts for carrying on induction (in the sense annexed to that term in a former chapter); for instituting experiments, altering the combination of circumstances by leaving out some or adding others, and watching the results; which operations are not reasoning, although reasoning, as before explained, must be, or may be, employed in conducting them.

They are to be regarded, in truth, as engaged in establishing the collective fact, or the premises from which inferences to new cases are to be drawn, or a general law is to be inferred.

When it is stated, for example, from an ample survey of the subject, that a certain cause has always, as far as observation has extended, produced a certain effect, this is not an inference or conclusion, but simply giving the summary result of inductive investigation.

When, however, we expect or predict, on a new occurrence of the cause, that the effect will follow,