tellectual powers and in respect to both is subjected to the laws of habit, and hence

"convinced against its will

Is of the same opinion still."

Hence the necessity of superadding other proofs; mainly that the native love of truth may have opportunity of rising by the contemplation of proof and triumphing over prejudice and aversion.

§ 141. Empirical proofs are divided into the following varieties:

First, EXPERIENCE;

Second, ANTECEDENT PROBABILITY;
Third, SIGNS;

Fourth, EXAMPLES.

§ 142. Of Empirical proofs, those from experience are the most weighty and decisive; but the use of them in reasoning is very limited.

The principal uses of this variety of proofs are 1. as materials for other varieties of proofs;

2. In rare cases to prove the particular facts to which they relate.

It will sometimes be the case that a speaker will need to prove a fact which has come within the personal experience of his hearers. In regard to intellectual and moral exercises as distinguished from mere sensations this appeal to such personal experience will ordinarily consist in a reference to the occasion on which the exercise was experienced; as the occasion may be remembered while the exercise itself may have escaped the notice of consciousness. Demosthenes thus proves to the Athenians that the policy which had in fact occasioned their disasters in the contest with Philip was

still a noble, just, worthy policy, by referring to the occa sions on which the feelings of the citizens actually burst out in generous indignation at the supposed treachery and artful ambition of Philip.

This variety of proofs is more commonly used as materials for other varieties of proof. They are thus used in two different ways; first, as distinct and independent proofs; secondly, as component parts of a complex body of proof. Thus the necessity of religion to the civil welfare and security of a nation might be forcibly proved to those in France who had lived through the terrific scenes of the Revolution by appeals to their own personal experience. One instance of such experience, perhaps, might not suffice for the proof. The repetition of those instances day after day for years would afford proof almost irresistible. Another illustration may be taken from Dr. South's argument to prove that other forms of government insensibly partake of monarchy and slide into it. He says, "For look upon any aristocracy or democracy, and still you shall find some one ruling active person among the rest who does every thing and carries all before him. Was not De Witt amongst our neighbors a kind of king in a commonwealth? And was not that usurper here amongst ourselves a monarch in reality of fact, before he wore the title or assumed the office?" *

§ 143. PROOFS FROM ANTECEDENT PROBABILITY are founded on the relations of a cause to its effect or of a general law to its particular results.

From the rise of the sap in the tree, thus, we infer, that there will be foliage, bloom, fruit and other particulars of vegetable growth. The circulation of the sap is, in this

*Discourse on Ps. 144, 10.

case, the cause which, unless something interfere to hinder its operation, will produce those effects. So observed diligence and integrity excite the confident expectation of thrift These are known causes of such a result.

and success.

Again, we believe from our knowledge of the laws of gravitation, that a heavy body unsupported will fall to the earth. Here we have no distinct perception of the particu lar cause of gravitation; we refer the phenomenon only to a law; and from our knowledge of the existence of the law, we affirm with unhesitating confidence that when the fit occasion is presented the proper operation of the law will be witnessed.

Whether the cause in operation or the law regulating it is more prominent in view, in this kind of proof, the nature of the proof is the same. There is, in both cases, ever implied a cause operating and a law governing its operations. Reference is generally made to the cause when it is known; to the law when the cause is unknown.

The validity of this proof rests on our conviction of the uniformity of the course of nature.

This variety of proof is frequently employed with great effect in questions of fact. It is the main reliance of Mr. Curran in his argument in defense of Finney. He employs with much force the perjured and corrupt character of the informer in the case as antecedent probability proof that the charge was groundless.

§ 144. The proof is of the nature of an antecedent probability proof when the absence of a sufficient operative cause is urged against the belief of a supposed event.

While from the laws of the mind we necessarily antici pate the appropriate effect from the observed operation of

a cause, so likewise, on the other hand, we reject the supposition of an event having occurred, if there be no proper cause to produce it. The absence of all motive to commit an imputed crime is thus esteemed a strong proof against the fact of its having been committed.

There is, properly speaking, no cause existing of a supposed event, when there is no opportunity afforded for its operation. In such a case, the cause is virtually wanting. If thus, there be a known ground for the probability of the commission of the crime in the character of the accused, yet if there be no possible opportunity for committing it, there is no operating cause; and the proof is as valid in this form as in the other where the non-existence of the cause itself is presented.

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Criminal trials abound with instances of this species of proof in both of its forms. A single exemplification will suffice to illustrate its nature and application. In the Goodridge case so called, Mr. Webster urges the want of all possibility of previous arrangement and concert, which the circumstances of the alleged crime presupposed, in proof of the innocence of the accused; while, on the other hand, he feels himself called to rebut the proof arising from the want of motive on the part of the prosecuting witness to feign a robbery.*

§ 145. The force of any given antecedent probability proof will depend on the degree of certainty in the connection between the cause and the effect.

If the cause be adequate to the effect and actually

* Webster's Speeches, Vol. II. In this case two men were tried on a charge of robbery committed on the person of Goodridge who was the prosecuting witness. The main reliance of the defense was that the robbery was a pretense.

operate, or no hindrance intervene, the proof is conclusive. If, on the other hand, there be uncertainty whether the cause actually operate, or whether it operate free from hindrance or interruption, the force of the proof will be so far impaired.

Where the proof lies in the absence of all cause for the supposed effect, the conclusion will be more or less certain according to the degree in which all causes or occasions possible in the case are excluded.

An important distinction is to be made between those antecedent probability proofs which are purely physical and such as are moral. A physical cause must operate when the occasion is presented. We infer with absolute certainty that water exposed will freeze when the temperature is below the freezing point. We cannot so certainly infer that a covetous man will steal or defraud when an opportunity is afforded; or that a threat of vindictive passion was actually followed by murder when occasion of executing it was presented.

§ 146. SIGNS are proofs which derive their force from the necessary dependence of one thing upon another. This dependence may be that of an event on its cause, or on the occasion or condition which is necessary in order to the operation of the cause to produce the supposed effect.

The sign is thus the dependent event or effect; the thing to be proved is the cause or occasion on which it depends.

The validity of this species of proof rests ultimately on the principle, received unhesitatingly by every mind, that every effect presupposes a cause and an occasion of its