1.
Degree of belief in a relation
between two types of events should reflect the observed frequency (probability)
with which the relation in question has held in the past.
2.
In
light of this, we obviously ought not to suppose that human testimony is
perfectly reliable. In particular, experience will have taught us to be
suspicious of it under a variety of circumstances: when witnesses contradict
each other, when the testifier’s self-interest is at stake, when the testifier
hesitates and back-tracks, when the testifier is un-naturally vehement; etc.
3.
When
someone testifies to something extraordinarily surprising, we need to weight
two probabilities against each other: the probability that the testifier is
mistaken, confused or lying, on the one hand, and the probability that the
extraordinary thing actually happened, on the other.
4.
A
miracle is, by definition, the most extraordinary possible sort of event: “violation of the laws of nature.” (A law
of nature is, for Hume, the record of a conjunction of events that has never failed to hold in our experience,
up to the report of the putative miracle.)
5.
Whenever
someone testifies to a miracle, we must therefore ask which is more probable:
that the testimony is false (for one or another reason), or that the miracle
actually occurred?
6.
Suppose
we had some reason to treat a particular piece of testimony as infallible. In
that case, if such testimony recounted a miracle, then we would have at best a stand-off, a situation in
which it would be rational to suspend any belief one way or the other.
7.
But
this situation never actually arises, because no testimony is ever infallible.
8.
Furthermore,
we know that people generally take delight both in believing, and in reporting,
astonishing things. This gives us special
reason to be suspicious when the most
astonishing possible sort of thing – a miracle – is reported.
9.
Furthermore,
when people report religiously significant miracles, they have reasons,
associated with their hopes for themselves and others, for convincing
themselves that they’re telling the truth. But this makes it still likelier
that they’re not.
10.
Furthermore,
most reports of religious miracles come to us at second or third or nth hand. We know from experience that
people enjoy repeating stories of miracles. So here is yet further grounds for
doubt.
11.
Indeed,
most miracles are reported to have occurred far away, either in space or time
or both. This means that even if the evidence for them was confuted at the
source, this confutation will likely not have reached us. Furthermore we know
from experience that, in general, the further back we go in history the more
extraordinary are the reported events. We can explain this by one of two
hypotheses: (i) earlier times were filled with magic, or (ii) pre-scientific
people will tend to report more miracles because they are, in general, more
credulous.
12.
Furthermore,
we don’t find reports of miracles on which everyone agrees. Since there are
multiple religions, there are multiples systems of mutually contradictory miracle
reports. The only rational course, under these circumstances, is to disbelieve
all of them.
13.
So
how do religions get started? Hume’s explanation is that at first, when their
numbers of converts are small, they aren’t important enough for it to be worth
people’s while to carefully refute the reports of miracles on which they are
based. By the time this is worth doing, because the religion has spread, it’s
generally too late, as the reported events have become too distant for direct
investigation.
14.
Thus
Hume concludes that it can never be rational to believe in any miracle, or to
endorse any religion on the basis of reports of miracles.
15.
Does
this reasoning apply to Christianity? Yes, says Hume. Thus, he concludes,
Christian belief must be based on `faith’ rather than reason.
16.
Many
Christians would say this same thing, but when Hume says it, it’s intended as a
sly way of declaring the religion to be nonsense. (He has to be sly about this:
had he not been, in his time and place, he would never have been able to obtain
a paid commission. Until the good sales of the book you’re reading, along with
his very successful History of England,
Hume partly earned his living as a kind of consultant.) But he gives away his
attitude for the careful reader at the very end of the section, when he offers
his definition of faith as follows: “Whoever is moved by Faith [the italics and the capital tell you he’s defining this] to
assent to it [Christianity] is conscious of a continued miracle in his own
person, which subverts all the principles of his understanding, and gives him a
determination to believe what is most contrary to custom and experience.” Hume
has just told us what he thinks of miracles – so, including the `continued
miracle in one’s own person’ – and we know from the opening sections of the
book that Hume regards reliance on anything other
than custom and experience as deluded. It’s thus quite clear that Hume
regards belief in Christianity, or any other religion, as absurd.