History and rare events

How probable is it that Jesus of Nazareth rose from the dead? James McGrath has been posting on this here and here, and quotes Bart Ehrman to the effect that it is utterly unlikely, and suggests that we cannot know by historical investigation whether such a thing happened. Each is articulating a religious opinion, of course, rather than anything on which scholarship as such has something to say, as they are entitled to do. 

It seems to me that these arguments only be made by making some assumptions which won’t bear examination.

Non-mathematicians frequently have difficulty with probability. Most people would imagine that if you flip a coin five times and it comes up heads each time, that it is more probable that next time it will come up tails. In truth the probability that it will come up heads remains unchanged at 50%.

We all know that miracles do not happen very often. That is a direct observation and may be taken as a fact. But the actual probability that any given event is a miracle must be unknown to us. We have no way to calculate this, for rare events.

I think that it would be useful here to stop talking about miracles specifically, and to discuss the general case: the “rare event” in history.  To discuss miracles brings in all sorts of prejudices which hamper the investigation.

Are we really being invited to say that rare events do not happen very often — indeed! — that what often happens must be what usually happens, and therefore, in loose terms based on gut feeling, that any given event other things being equal is “most likely” to be a common event than a rare one?

I think that we are — and so we are not saying something very profound here. Once we define an event as rare, we define it as “not usual.” This is just semantics. Most events in our lives are indeed commonplace.

But if we argue from rarity to what actually “must” be happening, doesn’t this involve the same fallacy as the coin-flipping earlier? There is a logical fallacy here. Surely it tells us precisely nothing as to whether a particular rare event did indeed happen, or whether a particular coin-toss will give one result or another. It only tells us a generality.

To argue that rare events never happen is a simply a mistake. For example, we all know that it is not very often that the taxman will give us a refund! We do not therefore presume that refunds never happen.

Dr McGrath would no doubt interject at this point that he doesn’t deny that miracles — rare events — might happen; only that we cannot know from studying the historical record if they do, since any evidence that appears is “more likely” to be a mistake than genuine.

Unfortunately the same logic applies to this argument. Can we never know if rare events occur? Imagine that a statement appears that in 2002 the taxman gave me a refund. Why should we ignore this? Surely we would sift the evidence?

In general, we should not do history by deciding in advance what is “most likely” to have happened in the past and then finding reasons to ignore whatever the evidence actually says. We need to let the historical record speak, and then assess that narrative in the light of other portions of the historical record. We may consider that a rare event did not in fact happen; but we should hardly decide this before considering the evidence. Still less should we refuse to consider evidence, on the grounds that an event is rare!

Now I am aware that some will be getting impatient with me here. They will feel that I am missing the point. I think that a common feeling is underlying all of this discontent, unstated, which I will now drag out of its hiding place and into the sunlight. It’s something like this:

“All religious claims that miracles happen are lies.”

or possibly

“Religious claims are more likely to be lies than other claims.”

We all find this feeling in our minds, whatever our beliefs. If we conduct a thought-experiment and imagine that a statue of the virgin spoke, the first instinct of all of us is a knee-jerk suspicion that it is a lie. But this is what we call a “prejudice”.

We need to decide whether we are doing history, or merely decorating our prejudice with snippets of historical data. It is no doubt the case that most references to miracles in classical texts are bogus. But if we intend to discover whether a specific miracle did or did not happen, we cannot simply appeal to this prejudice, which we might accept in cases where we are not directly investigating this issue. When we wish to decide whether a rare event did indeed happen, we must investigate it directly, rationally, and examine the evidence.

This is the problem with the kind of argument being made; that it evades the evidence in favour of a pre-judgement. No valid conclusion can be reached this way.

To argue that most miracles are fake therefore all miracles are fake is merely a prejudice. It tells us nothing about whether a given miracle was actually fake.

To argue that we cannot know whether any miracles are genuine because anyone who mentions one is “probably” lying is merely a form of words to express the same prejudice. What we think probable may be the only thing that we will believe; but if so, we will never learn anything that we do not already know.

Enough talk about “likely” or “probably”, disguising a non-rational secularism: for every event let us examine the data — all of the data — and go where it leads us. Scholarship can only advance when we address the difficult pieces of data, and open our minds.