ve said, habits of thought and feeling vary according to the epoch and
the environment.

"A comparison will be established between persons or things, in order to
be absolutely convinced of their degree of conformity.

"The state of mind in which we were when the previous events were
manifested will be considered, and we shall not fail to ascertain
plainly the similarity or change of humor at the moment as related to
that of the past.

"It is also of importance to observe the state of health, for under the
affliction of sickness things assume very easily a hostile aspect.

"It would be wrong to attribute to events judged during an illness the
same value which is given to them at this present moment.

"When one is absolutely decided as to the relation of new perceptions and
mental representations, one can calculate exactly the degree of
comparison.

"The moment will then have arrived to synthesize all the observations and
to draw from them the following deductions:

"First, like causes ought, all things being equal, to produce like
effects.

"Secondly, the event which is in question will therefore have the same
consequences as the previous one, since it is presented under the same
conditions.

"Or again:

"Being granted the principle that like causes produce like effects, as I
have just affirmed, and that there exist certain incompatibilities
between the contingencies of the past and those of to-day, one must allow
that these incompatibilities will produce different results.

"And, after this reasoning, the deductions will be established by
constituting a comparison in favor of either the present or past state
of things."

But the philosopher, who thinks of everything, has foreseen the case
where false ideas have obscured the clearness of the deductions, and he
said to us:

"The association of false ideas, if it does not proceed from the
difficulty of controlling things, is always in ungovernable opposition to
the veracity of the deduction.

"What would be thought of a man of eighty years who, coming back to
his country after a long absence, said, on seeing the family roof from
a distance:

"'When I was twenty years old, in leaving here, it took me twenty
minutes to reach the home of my parents, so I shall reach the threshold
in twenty minutes.'

"The facts would be exact in principle.

"The distance to be covered would be the same; but legs of eighty
years have not the same agility as those of ver