Atheism and Theism JJ Haldane - Common Sense Atheism

Atheism and Theism 53
that the original diagnosis was incorrect. Again, many diseases have spontaneous
remissions which are not regarded by medical experts as miraculous.
Furthermore our understanding of psychosomatic medicine may allow us to
explain some apparently miraculous cures of illness. Sometimes we doubt the
fact itself. The man raised from the dead may not really have been dead. On
the other hand, to allude to an example discussed by Hume, if a one-legged
man is reported to have been made two-legged, we judge that there must
have been some error in the testimony. There can hardly be misdiagnosis of
the number of a man’s legs, and there could be no medical or biological
explanation of the sudden sprouting of a previously amputated human leg.
Hume puts the point in too empiricist a way. He holds our doubt of the
report of such a sprouting of a leg to be ‘because it is contrary to our experience’.
The credulity and knavery of humankind (and perhaps love of the
marvellous for its own sake) provide a ready enough explanation. However,
by just saying ‘contrary to experience’ Hume does not do justice to the
importance of theory in our scientific background knowledge. Consider the explosion
of an asteroid eight kilometres above a fortunately uninhabited
part of Siberia early in this century, flattening trees over 2,200 square kilometres.
Fortunately the observation of such an occurrence is not a common
experience, but our knowledge of the astronomy of the solar system is such
that an occurrence of this sort is quite intelligible and to be expected to
occur occasionally.
We must remember that in his discussion of miracles Hume was not in
his mood of extreme epistemological scepticism, according to which anything
could be followed by anything. That is, Hume is not concerned with mere
logical inconsistency. Hume was of course aware that there is no logical
inconsistency in supposing that a one-legged man suddenly sprouted a new
second leg. We must suppose that Hume is concerned with physical possibility
or impossibility. Now our notion of physical possibility has to do with the
question of whether a phenomenon fits coherently into a web of belief. Of
course there are anomalies in science, but these are not regarded as miracles.
A good example from the past is that of the advance of the perihelion of
Mercury, which could not be fitted in with Newtonian mechanics and gravitational
theory, but which later was accommodated by the general theory of
relativity. Normally a scientist will not abandon a theory until there is a better
theory to replace it. (Compare Bruce Bairnsfather’s First World War cartoon,
of ‘Old Bill’ with another soldier sitting in a shell hole with all sorts of stuff
bursting around, and saying ‘Well, if you knows of a better ’ole, go to it’.)
Alternatively the scientist may be sceptical of reports of a refractory phenomenon.
People who are too empiricist, accepting observation reports too readily,
join forces in the credulity stakes with those who are not empiricist enough,
and are ready to believe any theory however inadequately it has been tested.