Wonderfully, the full text is available online through google books. The book is a collection of responses by various thoughtful people to the following request:
The Author of this letter, inspired by the untimely decease of a dear friend, and in contemplation of the numerous philosophical and logical theories leading to a belief in the continued existence of the soul, or personal identity after death, begs of you the great favor of a letter, setting out as briefly, or at such length as may be convenient, what you consider to be the strongest reason, or argument, advanced by science or philosophy, or by common sense, in favor of an affirmative answer to this mighty question; or preferably, a statement of your own deductions thereon.
It is our desire to obtain from thinkers and educators of the world, an expression—a twentieth century bulletin, on this subject.
Our request will impress you doubtless as an unusual one, but none the less will you see the force of it, and its possibilities. Who can measure the impetus such a compilation may have upon the inquiring human mind?
May I not have your co-operation in this matter?
Thanking you now in advance for the courtesy of a reply, I am
ROBERT J. THOMPSON.
Wellington Ave., Chicago, U. S. A.
I had fun skimming through the first collection of responses, from "The Scientists". The variety of responses is interesting. Although there's the usual bloviation on the cosmological and teleological arguments, as well as some self-citations to studies confirming the existence of telepathy and other paranormal phenomena, there's also some healthy scientific modesty. E.g., E. Ducleaux writes,
Excuse me for not being able to help you in your investigation. I have no scientific opinion regarding the questions you put. I mean, no opinion that rests on anything but personal beliefs. Besides, I think that everybody is in about the same position and that any reasons that may be brought forth in favor of one's opinion are only good for the person that brings them forth, and that they cannot impress the listener; they are therefore not scientific reasons.
D. I. Mendélieff's response begins similarly, although he ends by arguing for the immortality of the soul by analogy with the laws of conservation of mass and energy (an analogy I was surprised to see repeated very often in the other responses!):
The question as to the continuance of the existence of the soul or personal identity after death, mentioned in your letter of August, 1901, I, as a natural philosopher, consider to be an hypothesis which cannot be proved by evidence of real facts. But as a man educated in a religious sense, I prefer to remain in the belief of the immortality of the soul. It is my opinion that the philosophical side of the question consists in the relation between the soul, the natural forces, and matter; and if it were possible to clear up to some extent this feature of the problem---the relation between force and matter---then also the relation between the soul and natural forces would be forwarded to a great extent.
The unquestionable existence of reason, will and consciousness compels us to acknowledge the existence of a special world of relations of this kind, and any rational conclusion in relation to this special world cannot be accepted as proved quite in the same manner. Knowledge of physics and mechanics does not give anything in relation to chemistry or in relation to the existence of celestial bodies.
We must simply confess that it is impossible to comprehend this question in a general way, but it would also be sheer nonsense to ignore the physical world; and as matter and natural forces must be acknowledged as eternal, it is also probable that the soul is eternal.
But my favorite response was by James R. Nichols, marveling at the modern-day wonders of
Do we not every day converse with unseen friends long distances away; do we not recognize their familiar voices, in homes separated from us by rivers, woods, and mountains? These voices come out of the darkness, guided by a frail wire which science provides as a pathway.
If our friends in this life, dead to us (hidden as they are by the shroud of space), can be seen, and we can hear their voices, their shouts of laughter, the words of the hymns they sing, the cries of the little ones in the mother's arms, is it very absurd to anticipate a time when those dead to us by the dissolution of the body may, by some unknown telephony, send to us voices from a realm close at hand, but hidden from mortal vision?