'Miracles," said my friend. 'Oh, come. Science has knocked the bottom out of all that. We know that Nature is governed by fixed laws.’
‘Didn’t people always know that?’ said I.
‘Good Lord, no,’ said he. ‘For instance, take a story like the Virgin Birth. We know now that such a thing couldn’t happen. We know there must be a male spermatozoon.’
‘But look here’, said I, ‘St Joseph —‘
‘Who’s he?’ asked my friend.
‘He was the husband of the Virgin Mary. If you’ll read the story in the Bible you’ll find that when he saw his fiancée was going to have a baby he decided to cry off the marriage. Why did he do that?’
‘Wouldn’t most men?’
‘Any man would’, said I, ‘provided he knew the laws of Nature — in other words, provided he knew that a girl doesn’t ordinarily have a baby unless she’s been sleeping with a man. But according to your theory people in the old days didn’t know that Nature was governed by fixed laws. I’m pointing out that the story shows that St Joseph knew that law just as well as you do.’
‘But he came to believe in the Virgin Birth afterwards, didn’t he?’
‘Quite. But he didn’t do so because he was under any illusion as to where babies came from in the ordinary course of Nature. He believed in the Virgin Birth as something supernatural. He knew Nature works in fixed, regular ways: but he also believed that there existed something beyond Nature which could interfere with her workings — from outside, so to speak.’
‘But modern science has shown there’s no such thing.’
‘Really,’ said I. ‘Which of the sciences?’
‘Oh, well, that’s a matter of detail,’ said my friend. ‘I can’t give you chapter and verse from memory.’
‘But, don’t you see’, said I, ‘that science never could show anything of the sort?’
‘Why on earth not?’
‘Because science studies Nature. And the question is whether anything besides Nature exists — anything “outside”. How could you find that out by studying simply Nature?’
C.S. Lewis, "Religion and Science," God in the Dock (Eerdmans: 1970) 72-73.