o at the end of, say 'every ten thousand years,' all the
same events which have been happening throughout the period may begin
to happen over again in the same order as before. Such a succession,
however, would involve quite as much of retrogression as of progression,
and the continual advance so boastfully spoken of would be nothing else
than a tendency of society to return to the condition from which it had
originally emerged. But, even on this uncomfortable hypothesis, there
could be no regularity of occurrences within the same cycle; no clue as
to the future could be obtained from investigation of the past. On the
contrary, the only certainty would then, as now, be that no combination
of events which had happened once could happen again, as long as the
existing order of things continued. The inference here follows
necessarily from the premises. If there be continual advance--if things
are constantly moving forward--they cannot remain in the same state; and
if not in the same state, they cannot produce the same effects. For, if
it be obvious, on the one hand, that precisely the same causes must
invariably produce the same results, it is equally evident, on the
other, that the same results cannot be reproduced except by the same
causes. If causes calculated to bring about certain phenomena undergo
either augmentation or diminution, there must be a corresponding change
in the phenomena. Now, effects cannot be identical with their causes,
and, in the moral world, effects once produced become in turn causes,
acting either independently or in conjunction with pre-existing causes.
They become in turn the antecedents spoken of by Mr. Buckle, from which
spring the motives of human conduct. But, as all such antecedents must
necessarily differ from all former antecedents, they must also give rise
to motives, must be followed by actions, and must bring about
combinations of circumstances, differing from any previously
experienced. Thus, in human affairs, there can be no recurrence either
of antecedents or of consequences; and, as a scientific law is simply a
record of the uniform recurrence of consequences, it follows that in
human affairs there can be no scientific laws.

It will be understood that human conduct, and the circumstances or
causes which influence it, are here spoken of in the aggregate. It is
not pretended that particular causes or circumstances may not continue
permanently in operation, though with an influence m