This premise once laid down, the conclusion would be reached; all the
more exact, because, without abandoning their arguments, each one would
present those which it is easy to turn against an adversary.

Before solving a problem, he who desires to avoid making a mistake must
never fail to ask himself this question:

What should I do if my interests were those of the opposite party?

Or, yet again:

What should I reply if my adversaries used the same language to me as I
purpose using when addressing them?

This method is valuable in that it raises unexpected objections, which
the mind would not consider if one had simply studied the question from
one's own point of view.

It is a self-evident fact that, according to the state of mind in which
we are, things assume different proportions in the rendering of
judgment on them.

We must not argue as children do, who, not having the sense of
calculating distances, ask how the man standing near to them will be able
to enter his house, which they see far away, and which seems to them of
microscopic dimensions.

One departs from common sense when one attributes to insignificant things
a fundamental value.