Otago Institute. 565 
must follow, matters must be looked at all round before an attempt is made to establish 
a conclusion. We have to arrive at something like a general proposition from particular 
ones, instead of the logically more certain process of deducing the particular from a 
general. The reason of this it is easy to see. In the physical sciences the particular 
premises are more within our cognizance than the general ones. Thus the two tempta- 
tions, against which I have presumed to warn students, have their root in the same 
circumstance. To try to arrive at a scientific conclusion from a general theory is to try 
to get a certainty out of an uncertainty; and to hastily frame a general proposition out 
of a small array of observations, even supposing them to be correct enough in themselves, 
is to make the same mistake by an opposite method. An induction can never do more 
than justify a reasonable conviction of the mind, and afford the highest probability of 
the truth of the conclusion, but there is always the possibility of that conclusion being 
modified by the presentation of further particulars, beforetime unknown or neglected. 
You see, then, what a multitude of lines ought to converge before a positive assertion is 
ventured upon—in other words, before this or that is affirmed to be scientific fact. I 
have alluded, by way of illustration, to the question of the duration of man upon the 
face of the earth ; I then used it in speaking of the quality of evidence, and of the happy 
knack some have of making a very little go a long way. I press the same question into 
my service in pointing out how frequently considerations which have an important 
bearing upon the subject in hand are passed by without fair consideration, possibly from 
a kind of intuition that they will prove to be lines which will not converge to the 
conclusion we would fain see established; it is so very hard to be quite unbiassed, and 
free from all party influences! In debates upon the question I have named, it has never 
appeared to me that sufficient attention has been given to the enormous possibilities 
within the period acknowledged by all. Iam not now insisting upon the correctness of 
the most generally-accepted reckonings in Bible chronology, nor am I entering upon the 
merits of the question I allude to; but speaking of time as an element in such questions, 
I think that no sufficient recognition is made of all that a thousand years may mean. 
Realize in mind the condition, say of Britain and Northern Europe generally, 1,000 years 
ago, with reference to the condition of its population, climate, forests, wild animals, and 
the like; go back then in mind 1,000 years before that again, and, repeating this process, 
I think it will be seen that, when enormous periods of time are glibly rolled off the 
tongue in relation to such questions, there is not unfrequently a failure to apprehend the 
full force of what is so easily dismissed, and perhaps, after all, it will be thought that the 
premises which may have been fairly established are not numerous enough, viewed in 
the light of other considerations, to enable anything like a positive assertion to be made. 
I must say a few words upon that alluring snare of over-systematizing in scientific 
matters. It is so very satisfactory to be able to announce a law; it seems one step more 
towards reducing confusion to order, it seems to be getting something done and settled ; 
but here again we may be only pushing our particular to a universal. A conclusion in 
geological science, for example, which is just enough when confined to one locality, is 
utterly fallacious when stretched out into universality. These remarks will apply, in 
my estimation, to such artificial arrangements as the division of the human period into 
e stone, the iron, and the bronze periods. Whatever justification there may be for 
such a division in a particular country, it cannot consistently with history be predicated 
in application to the world ai large. Every day long-buried treasures are being brought 
to light which tell us that as far back as the historie eye can pierce there were nations 
Who had attained a high degree of knowledge and of skill in the working of metals, and 
if to the testimony derived from the most ancient cities of Assyria or Greece we may 
