There is however a positive side to the question.
I believe that so far from being antagonistic to Christian teaching, the general acceptance of the hypothesis would be of real value, in that it would put into the hands of the Church a very powerful weapon for the repelling of a certain form of attack, that of the scientific materialist to wit.
I do not mean to claim this as a merit of the four-dimensional hypothesis as such, for it would equally accrue to any other hypothesis which might prove to be true.
In the second chapter I gave my reasons for believing that the establishing of some such hypothesis would be calculated to remove the principle cause of dissension between religious and materialistically scientific thinkers. I there pointed out that the chief strength of the materialist lay in the reluctance or inability of the Church to give an intelligible explanation of the terms used in speaking of certain religious and spiritual matters.
I have explained that I see nothing in anyway repugnant to religion in the attempt to formulate an hypothesis to explain the mechanism of survival, etc.
Equally it should be observed that religion, considered as something more than a mere ethical and moral code, would be in no way freed from the necessity of justifying itself, qua religion, by the acceptance, however unanimous, of this or any other hypothesis. Such justification is a matter for an apologetic of quite another order, of which order, by the way, I regard Mr. Chesterton's "Orthodoxy" mentioned above as a very admirable example.
What the general acceptance of such an hypothesis would do, would be finally and for ever to deprive the materialist of the possibility of maintaining that matter, as he knows it, is the final and only permanent reality and that Spirit therefore cannot exist.
It is true that this would only involve driving him back one stage. If we suppose for the sake of argument that we could finally attain to as complete a knowledge of the "next world" as we at present possess of this, he could always return to the attack, using with regard to that state the same arguments as he originally used with regard to this. But having once broken through the ring fence of matter and demonstrated that there exist other realities of which he was at one time entirely ignorant, he could never deny that there might still be realms as yet unknown to him. He could never catch us again, so to speak.
I admit that the above is a somewhat fantastical supposition and scarcely within the sphere of practical politics, but the point is, that until we are prepared to give an intelligible explanation of things we are pent up in a sort of intellectual cul-de-sac bounded by matter. We may know, as the result of personal experience, that there is a way out, that matter is not the only reality; but our knowledge is a purely personal affair and the scientist is perfectly entitled, if he wishes, to decline to take the steps that led to the experiences which have convinced us, to dismiss them as mere hallucinations and to write off our alleged "revelations" as superstitious myths.
But let us once demonstrate to him, in a manner calculated to appeal to his intellect, that there may be a non-material reality and the cul-de-sac is at once broken through and becomes a vista.