45 
unity called a law of nature ; but if the latter, we inevitably 
sink to the pernicious occupation of constructing bubble 
theories, and add some more to the already too long list of the 
fallacies of philosophers. 
A scientific is somewhat like a judicial court, where the pur- 
pose is to obtain a verdict ; in other words, to procure informa- 
tion regarding the subject in dispute. The jury must see that 
they have sufficient evidence on which to base a verdict of any 
kind; secondly, that they have all the evidence before them 
which is procurable ; and thirdly, that the verdict be according 
to the evidence. The naturalist also, before he can say he has 
discovered a fact or a law, must act in a similar manner. While 
the evidence is all on one side, the way is clear ; but when it 
becomes conflicting, only the greatest care, strictest impartiality, 
and most thorough training can sift the false from the true, 
and decide the matter rightly ; but even then it is not always 
possible. 
There lies in this a strong temptation to concentrate our 
attention on those facts alone which favour the theory we wish 
to establish, excluding all others from our thoughts. This may 
be theory-manufacture, but it is not science. Let the confusion, 
or difficulty, be increased ever so much, the naturalist must 
search thoroughly, impartially, and critically, if he would have 
his science true, and his knowledge real. 
Science, then, begins with facts obtained either by observa- 
tion or experiment, passes on to inferences from these facts, 
which inferences, if conducted rightly, according to the laws of 
thought, will be as true as their premises ; so that we end with 
facts as we began with them. 
The first step consequently in the procuring of adequate 
evidence for scientific purposes is the obtaining of facts, mostly 
by observation. This seems an easy matter to those who are 
unaccustomed to the task. “ W hat simpler,’’ they say, “ than to 
look, and tell what you have seen? ” It is, however, so diffi- 
cult, that the well-known saying is unfortunately true, “ that 
there are more false facts than false theories in the world.” 
The reason of this is that we confound our observations with 
our inferences, for observation is never a simple passive process 
of the senses, but is always accompanied by some active mental 
state. We think while we look. We consequently contribute 
to the observation something from ourselves, uniting the sub- 
jective and the objective into one. This mental addition very 
frequently is a prejudice; we ai’e not content with trying to 
discover what is, but look out for what we imagine ought to be, 
or what we want to be. It would be very difficult, for example, 
