It is natural to think that miracles can, in principle, provide some evidence in favor of religious belief. Suppose that we think of a miracle as an event which is an exception to the laws of nature. Then, if we see such an event, we might be justified in thinking that it does not have a natural cause. But, especially if we think that every event has some explanation, one might reasonably conclude that it has a supernatural cause. But if it has a supernatural cause, then something supernatural must exist.
An advantage of this sort of ‘argument from miracles’ over more abstract arguments, like the design and cosmological arguments: a response to Hume’s charge that these leave their proponent to to“fix every point of his theology by the utmost license of fancy and hypothesis.”
How might this be turned into a justification for religious belief even for people who do not witness miracles? The role of testimony in belief formation and justification.
It seems clear that, in at least many religious traditions, people have based their belief in something like this sort of argument from miracles. In the selection from Pascal, we get a very strong statement of this view:
811. Had it not been for the miracles, there would have been no sin in not believing in Jesus Christ.
812. I should not be a Christian, but for the miracles, said Saint Augustine.
Pascal situates the question of miracles within (one part of) the Christian tradition. But the question we want to answer is more general: can miracles play this kind of central role in justifying religious belief of any sort?
We will focus on the question of whether miracles can justify the religious beliefs of people who have not themselves witnessed miracles.
Hume thinks that they cannot, and indeed that no rational person would base belief in God on testimony that miracles have occurred. He says:
“...therefore we may establish it as a maxim, that no human testimony can have such force as to prove a miracle, and make it a just foundation for any system of religion.” (88)
This is Hume’s conclusion. We now need to understand his argument for it, which begins with some premises about the role of perceptual evidence and testimony in the forming of beliefs.
Hume’s first claim is that we should base belief on the available evidence:
“A wise man, therefore, proportions his belief to the evidence. ...He weighs the opposite experiments: He considers which side is supported by the greater number of experiments: To that side he inclines, with doubt and hesitation; and when at last he fixes his judgement, the evidence exceeds not what we properly call probability.” (73-4)
The general moral seems to be correct: when deciding whether to believe or disbelieve some proposition, we should weigh the evidence for and against it to see whether it makes the proposition or its negation more probable.
How does this sort of general principle fit with our practice of basing beliefs on testimony? Hume has a very plausible answer:
“we may observe, that there is no species of reasoning more common, more useful, and even necessary to human life, than that which is derived from the testimony of men, and the reports of eye-witnesses and spectators. ...I shall not dispute about a word. It will be sufficient to observe, that our assurance in any argument of this kind is derived from no other principle than our observation of the veracity of human testimony, and of the usual conformity of facts to the reports of witnesses.” (74)
One conclusion: testimony is one, but not the only, source of evidence which we should use when forming a belief. Testimony is relevant because it has a (relatively) high probability of being true. But, like any evidence, this can be overridden by other sources of evidence (like, for example, contrary testimony) which have give a high probability to the negation of the proposition in question.
We now need to apply these general points about testimony and evidence to the case of miracles. One conclusion seems to follow immediately:
“That no testimony is sufficient to establish a miracle, unless the testimony be of such a kind, that its falsehood would be more miraculous, than the fact, which it endeavors to establish ...” (77)
The problem for the believer in miracles is that miracles, being departures from the laws of nature, seem to be exactly the sorts of events which we should not expect to happen. As Hume puts it:
“A miracle is a violation of the laws of nature; and as a firm and unalterable experience has established these laws, the proof against a miracle, from the very nature of the fact, is as entire as any argument from experience can possibly be imagined ...There must be a uniform experience against every miraculous event, otherwise the event would not merit that appellation.” (76-7)
The implied question is: could testimony ever provide strong enough evidence to override our massive evidence in favor of nature’s following its usual course (which is also evidence against the occurrence of the miracle)?
In §II, Hume adds another reason to be skeptical about testimony about miracles, when he writes
“there is no testimony for any [miracles] ...that is not opposed by an infinite number of witnesses; so that not only the miracle destroys the credit of testimony, but the testimony destroys itself. To make this better understood, let us consider, that, in matters of religion, whatever is different is contrary ...Every miracle, therefore, pretended to have been wrought in any of these religions (and all of them abound in miracles) ...has the same force ...to overthrow every other system.” (81)
Is this best construed as a separate argument against miracles, or as part of the argument sketched above? If the latter, how does it fit in?
So far we have only been discussing Hume’s argument against beliefs in miracles which are based on testimony by (people who claim to be) eyewitnesses. But what about people who (seem to) witness miracles? Are they justified in forming religious beliefs on the basis of such experiences? Can you think of an extension of Hume’s argument which would apply to this case?
The question of whether Hume’s argument presents an ‘in principle’ way of discounting any testimony in a miracle, or whether it just provides a set of considerations which we should bring to bear in evaluating instances of such testimony. Hume seems to think, in at least some places, that it accomplishes the first more ambitious goal. Other ways of stating his conclusion are open to either interpretation, as when he says
“I flatter myself, that I have discovered an argument ...which, if just, will ...be an everlasting check to all kinds of superstitious delusion, and, consequently, will be useful as long as the world endures.” (73)
There is good reason to be skeptical about the more ambitious version of Hume’s claim, for we would need to know that there can be no case in which the occurrence of the miracle would be more unlikely than the unreliability of the testimony. Two points of relevance to this: (i) the role of multiple witnesses, and (ii) the role of prior probabilities.
(If you are interested in a very critical but interesting discussion of Hume’s argument which situates it in the context of contemporary debate about probability and miracles, you should read John Earman’s Hume’s Abject Failure.)