The question for man most momentous of all is whether or no he has an immortal soul; or—to avoid the word immortal, which belongs to the realm of infinities—whether or no his personality involves any element which can survive bodily death. In this direction have always lain the gravest fears, the farthest-reaching hopes, which could either oppress or stimulate mortal minds.

On the other hand, the method which our race has found most effective in acquiring knowledge is by this time familiar to all men. It is the method of modern Science—that process which consists in an interrogation of Nature entirely dispassionate, patient, systematic; such careful experiment and cumulative record as can often elicit from her slightest indications her deepest truths. That method is now dominant throughout the civilised world; and although in many directions experiments may be difficult and dubious, facts rare and elusive, Science works slowly on and bides her time,—refusing to fall back upon tradition or to launch into speculation, merely because strait is the gate which leads to valid discovery, indisputable truth.

I say, then, that this method has never yet been applied to the all-important problem of the existence, the powers, the destiny of the human soul.

Nor is this strange omission due to any general belief that the problem is in its nature incapable of solution by any observation whatever which mankind could make. That resolutely agnostic view—I may almost say that scientific superstition—"ignoramus et ignorabimus"—is no doubt held at the present date by many learned minds. But it has never been the creed, nor is it now the creed, of the human race generally. In most civilised countries there has been for nearly two thousand years a distinct belief that survival has actually been proved by certain phenomena observed at a given date in Palestine. And beyond the Christian pale—whether through reason, instinct, or superstition—it has ever been commonly held that ghostly phenomena of one kind or another exist to testify to a life beyond the life we know.

But, nevertheless, neither those who believe on vague grounds nor those who believe on definite grounds that the question might possibly be solved, or has actually been solved, by human observation of objective facts, have hitherto made any serious attempt to connect and correlate that belief with the general scheme of belief for which Science already vouches. They have not sought for fresh corroborative instances, for analogies, for explanations; rather they have kept their convictions on these fundamental matters in a separate and sealed compartment of their minds, a compartment consecrated to religion or to superstition, but not to observation or to experiment.

It is my object in the present work—as it has from the first been the object of the Society for Psychical Research, on whose behalf most of the evidence here set forth has been collected,—to do what can be done to break down that artificial wall of demarcation which has thus far excluded from scientific treatment precisely the problems which stand in most need of all the aids to discovery which such treatment can afford.

Yet let me first explain that by the word "scientific" I signify an authority to which I submit myself—not a standard which I claim to attain. Any science of which I can here speak as possible must be a nascent science—not such as one of those vast systems of connected knowledge which thousands of experts now steadily push forward in laboratories in every land—but such as each one of those great sciences was in its dim and poor beginning, when a few monks groped among the properties of "the noble metals," or a few Chaldean shepherds outwatched the setting stars.

What I am able to insist upon is the mere Socratic rudiment of these organisms of exact thought—the first axiomatic prerequisite of any valid progress. My one contention is that in the discussion of the deeper problems of man's nature and destiny there ought to be exactly the same openness of mind, exactly the same diligence in the search for objective evidence of any kind, exactly the same critical analysis of results, as is habitually shown, for instance, in the discussion of the nature and destiny of the planet upon which man now moves.

Obvious truism although this statement may at first seem, it will presently be found, I think, that those who subscribe to it are in fact committing themselves to inquiries of a wider and stranger type than any to which they are accustomed;—are stepping outside certain narrow limits within which, by ancient convention, disputants on either side of these questions are commonly confined.

A brief recall to memory of certain familiar historical facts will serve to make my meaning clearer. Let us consider how it has come about that, whereas the problem of man's survival of death is by most persons regarded as a problem in its nature soluble by sufficient evidence, and whereas to many persons the traditional evidence commonly adduced appears insufficient,—nevertheless no serious effort has been made on either side to discover whether other and more recent evidence can or cannot be brought forward.