The universe has come into existence somehow or other, and the
problem is, whether it came into existence in one fashion, or
whether it came into existence in another; and, as an essential
preliminary to further discussion, permit me to say two or three
words as to the nature and the kinds of historical evidence.

The evidence as to the occurrence of any event in past time may
be ranged under two heads which, for convenience' sake, I will
speak of as testimonial evidence and as circumstantial evidence.
By testimonial evidence I mean human testimony; and by
circumstantial evidence I mean evidence which is not human
testimony. Let me illustrate by a familiar example what I
understand by these two kinds of evidence, and what is to be
said respecting their value.

Suppose that a man tells you that he saw a person strike another
and kill him; that is testimonial evidence of the fact of
murder. But it is possible to have circumstantial evidence of
the fact of murder; that is to say, you may find a man dying
with a wound upon his head having exactly the form and character
of the wound which is made by an axe, and, with due care in
taking surrounding circumstances into account, you may conclude
with the utmost certainty that the man has been murdered;
that his death is the consequence of a blow inflicted by another
man with that implement. We are very much in the habit of
considering circumstantial evidence as of less value than
testimonial evidence, and it may be that, where the
circumstances are not perfectly clear and intelligible, it is a
dangerous and unsafe kind of evidence; but it must not be
forgotten that, in many cases, circumstantial is quite as