The Method by which the Causes of the Present and Past Conditions of Organic Nature Are to Be Disco | Page 8

not suspended
during the night? It may be that there has been some kind of

supernatural interference in this case." In point of fact, he declares that
your hypothesis is one of which you cannot at all demonstrate the truth,
and that you are by no means sure that the laws of Nature are the same
when you are asleep as when you are awake.
Well, now, you cannot at the moment answer that kind of reasoning.
You feel that your worthy friend has you somewhat at a disadvantage.
You will feel perfectly convinced in your own mind, however, that you
are quite right, and you say to him, "My good friend, I can only be
guided by the natural probabilities of the case, and if you will be kind
enough to stand aside and permit me to pass, I will go and fetch the
police." Well, we will suppose that your journey is successful, and that
by good luck you meet with a policeman; that eventually the burglar is
found with your property on his person, and the marks correspond to
his hand and to his boots. Probably any jury would consider those facts
a very good experimental verification of your hypothesis, touching the
cause of the abnormal phenomena observed in your parlour, and would
act accordingly.
Now, in this suppositious case, I have taken phenomena of a very
common kind, in order that you might see what are the different steps
in an ordinary process of reasoning, if you will only take the trouble to
analyse it carefully. All the operations I have described, you will see,
are involved in the mind of any man of sense in leading him to a
conclusion as to the course he should take in order to make good a
robbery and punish the offender. I say that you are led, in that case, to
your conclusion by exactly the same train of reasoning as that which a
man of science pursues when he is endeavouring to discover the origin
and laws of the most occult phenomena. The process is, and always
must be, the same; and precisely the same mode of reasoning was
employed by Newton and Laplace in their endeavours to discover and
define the causes of the movements of the heavenly bodies, as you,
with your own common sense, would employ to detect a burglar. The
only difference is, that the nature of the inquiry being more abstruse,
every step has to be most carefully watched, so that there may not be a
single crack or flaw in your hypothesis. A flaw or crack in many of the
hypotheses of daily life may be of little or no moment as affecting the
general correctness of the conclusions at which we may arrive; but, in a
scientific inquiry, a fallacy, great or small, is always of importance, and

is sure to be constantly productive of mischievous, if not fatal results.
Do not allow yourselves to be misled by the common notion that an
hypothesis is untrustworthy simply because it is an hypothesis. It is
often urged, in respect to some scientific conclusion, that, after all, it is
only an hypothesis. But what more have we to guide us in nine-tenths
of the most important affairs of daily life than hypotheses, and often
very ill-based ones? So that in science, where the evidence of an
hypothesis is subjected to the most rigid examination, we may rightly
pursue the same course. You may have hypotheses and hypotheses. A
man may say, if he likes, that the moon is made of green cheese: that is
an hypothesis. But another man, who has devoted a great deal of time
and attention to the subject, and availed himself of the most powerful
telescopes and the results of the observations of others, declares that in
his opinion it is probably composed of materials very similar to those
of which our own earth is made up: and that is also only an hypothesis.
But I need not tell you that there is an enormous difference in the value
of the two hypotheses. That one which is based on sound scientific
knowledge is sure to have a corresponding value; and that which is a
mere hasty random guess is likely to have but little value. Every great
step in our progress in discovering causes has been made in exactly the
same way as that which I have detailed to you. A person observing the
occurrence of certain facts and phenomena asks, naturally enough, what
process, what kind of operation known to occur in nature applied to the
particular case, will unravel and explain the mystery? Hence you have
the scientific hypothesis; and its value will be proportionate to the care
and completeness with which its basis had been tested and