The doubts which have arisen concerning events of this kind have their roots on the one hand in the apparent absence of such occurrences in our day, on the other in the fact that the laws of nature derived by science from the present condition of the world seem to rule them out.⁵ In the light of the concept of the world's 'ageing' which we have tried to develop here, not only do the relevant reports become plausible, but it also becomes understandable why, if such events have taken place in the past, they fail to do so in our own time.