In ordinary thinking we recognize a link between what we call cause and effect. A particular act of conscious will, or a particular set of circumstances, are likely to lead to predictable outcomes. Without some kind of such predictability, life and communication would both be impossible. “Science” systematically explores such natural cause-effect links in detail, explaining how past circumstances led to particular outcomes, and predicting how future outcomes will occur.
But what exactly is the link between cause and effect in nature? It can be argued that eg “2+2=4” is necessarily true, so to deny it would be self contradictory. So is the link between cause and effect like this? Would it be self-contradictory to imagine that on some occasion the cause-effect link did not occur? No it would not. Suppose, for example, that we know that in general an element with an atomic weight of 63.546 (which we call copper) conducts electricity. However many times we can observe this, there would be no logical contradiction in supposing that the next time we try it our piece of the element will not conduct. A scientific law is at most a generalization about what is normally observed to occur; and a description of normal occurrences could never dictate to us whether or not there could be abnormal ones. To use a crude analogy: to say that man is a biped is not to deny humanity to someone who has a wooden leg.
Now if the bible had said that virgin births were an everyday event, then we might check this by scientific observation. If it says that one such birth occurred as a unique event in history, then no generalization in science could be relevant. One cannot disprove a claim that 2000 years ago an unusual or unique event took place by showing that such events do not happen every day.
Now it is true both that (i) in general we do experience regularity in natural sequences, and (ii) that we have to seek and find such regularity in order to live and communicate. Normally everyone knows, for example, that water does not turn into wine. All that science does is to add further levels of detail to this generalizations from observation. Alcohol is produced when yeasts alter sugar in the absence of oxygen to produce 2CH3CH2OH. Carbon atoms have to be added to the hydrogen and oxygen atoms in water, and formed into specific alcohol molecules. This cannot normally be done by pouring out water or H2O. But all that science has done here is to add detail to the normal observation: pouring out water never produces alcohol. It cannot show that there is some logical impossibility in such an event. The fact that carbon atoms do not usually appear from nowhere is itself only a conclusion from observation.
So do miraculous events like this ever actually happen? To answer this we need to note that there is a complex relationship between observation, belief, and world-view. “Seeing is believing” is not necessarily true – what we see is interpreted to “make sense” according to our world-view. For any such apparent event there are always several possibilities. Suppose that a someone apparently produces wine from water. There seems no conceivable way this could happen within natural cause-effect sequences; so either: (1) It really has happened and there has been a break in natural laws, or (2) It was a trick or a hallucination.
If the person is a magician/entertainer then, whatever our world view, we could make no sense of them really being able to do this, so would conclude it was a trick or hallucination.
But suppose that the person is Jesus of Nazareth?
For a materialist-atheist observer like eg Daniel Dennett, because there is no reality outside the physical one, any break in physical cause-effect would be purely arbitrary and senseless. Such a person would therefore have little option but to conclude it was a mistake, trick or hallucination.
It would be different for a Christian observing such an apparent event because Christians believe that God is not merely a cause alongside other causes but at a different level of causality is the cause of everything continuing to exist. God ‘holds together the universe by his word of power’ (Hebrews 1:3), that is, anything exists only because of his continued will that it should. For life to be possible at all, such a God has to maintain a fairly regular sequence of cause-effect, but there is no need for it to be absolute. Within such a world view there is nothing irrational in supposing that sometimes God could vary the pattern for higher purposes. Normally, water does not become wine, but to make a special point about his unique manifestation in Jesus there is no reason God could not do it. It would be a “miracle” – not simply an inexplicable occurrence, but one in which higher considerations required a departure from normal cause-effect. If that Christian observer happened to be a scientist it would make no difference at all.
Similar considerations apply when we see similar apparent miracles today. Actually science has made the evidence for such things stronger not weaker, because diagnosis is now more certain. A sudden, scientifically inexplicable, disappearance of a cancer tumor would be just an inexplicable event to an atheist but is a “miracle” to a Christian. And such instances do happen sometimes. However, no miracle could ever be an absolute knock-down proof that God existed and that Jesus was his Son. Virtually anything could be explained away someone as a trick, a hallucination, etc, by a sufficiently determined atheist.
Some further points.
Firstly, God works through miracles but also through natural causal sequences. Jesus said it is God who feeds the birds (Matthew 6:26) but God does it through the regular cause-effect sequences of nature. Laws of nature are not independent of God but just describe his usual way of working. From our modern standpoint we might want to distinguish two different kinds of “miracle”:
Type 1 miracles: where there is miraculous timing but it may be possible that natural cause-effect sequences have applied (eg the plague of flies sent on Egypt)
Type 2 miracles: where there is no conceivable cause-effect sequence to explain it (eg water turning into wine)
This distinction goes back at least to the early fifth century, but is not in the Bible itself. The New Testament generally uses two words for miracle - “sign” and “power” and is not concerned with whether God is working within natural processes or in suspension of them. Its concern is just that (i) it is a noteworthy or very unusual event (ii) God has a special intention in it.
Thus if eg we conclude that when Jesus stilled the waves (Mark 4:49) there was no departure from normal cause-effect sequence, it would not be the less a sign and wonder in New Testament terms.
Secondly, it is always the job of science to seek a natural explanation ie an explanation using normal cause-effect sequences. Thus eg if a cancer has disappeared it is the scientist’s job (whatever his or her personal world-view) to seek a natural explanation. There is nothing anti-Christian about this, and, indeed, if a “natural” explanation is found, a Christian will not the less praise God for the healing and recovery. It is just that a scientist who is a Christian may be prepared to admit that there are some occasions when science simply cannot find any plausible cause-effect explanation, and a supernatural miracle seems the most logical conclusion.
Finally, the strong idea of cause-effect, sometimes called the mechanical philosophy, was essential to science. Foremost amongst its early advocates were men like Robert Boyle (1627-1691) – a founder of modern chemistry and of the Royal Society. Boyle was a devout Christian, fluent in biblical languages, who strongly believed in the Biblical miracles. As a believer in a God who held the universe together by his word of power Boyle had no problem at all in this. Neither should we.