It would be difficult to find truer thought better expressed. It is the language of true science, and is also the expression of the highest philosophy.
CHAPTER X
SUNDRY EXPERIMENTS AND OBSERVATIONS
Abundant testimony as to the existence of a hitherto little explored psychic realm has doubtless been given in the preceding pages. Mediumistic phenomena proclaim the existence of unknown forces. It is almost superfluous to heap up in this place a still greater number of recorded instances.
However, these facts are so extraordinary, so incomprehensible, so hard to believe, that a mere increase in the number of cases is not without value, especially when they are furnished by men of incontestable skill and learning. The old law proverb Testis unus, testis nullus ("One witness is no witness") is applicable here. We must not verify once, we must verify a hundred times, such apparently scientific extravagances, in order to make sure they are not delusions, but sober facts.
In short, the whole subject is so curious, so strange that the investigator of these mysteries is never surfeited.
Hence, in addition to what has already been given, I shall select and present in this place, out of the immense collection of observations which I have for a long time been making, those which most strike the attention and give added confirmation to what has preceded.
In addition to the experiments of Crookes, it is fitting to add in this place those of the great English naturalist, Alfred Russel Wallace, also a member of the Royal Society of London, President of the English Anthropological Society, and well known as the scientist, who at the same time with Darwin (June, 1858), gave to the world the theory of the variation of species by natural selection.