taunt each other either with following the false impressions of
childhood or with running rashly after the new. Who keeps the due mean?
Let him appear and prove it. There is no principle, however natural to
us from infancy, which may not be made to pass for a false impression
either of education or of sense.

"Because," say some, "you have believed from childhood that a box was
empty when you saw nothing in it, you have believed in the possibility
of a vacuum. This is an illusion of your senses, strengthened by custom,
which science must correct." "Because," say others, "you have been
taught at school that there is no vacuum, you have perverted your common
sense which clearly comprehended it, and you must correct this by
returning to your first state." Which has deceived you, your senses or
your education?

We have another source of error in diseases.[52] They spoil the judgment
and the senses; and if the more serious produce a sensible change, I do
not doubt that slighter ills produce a proportionate impression.

Our own interest is again a marvellous instrument for nicely putting out
our eyes. The justest man in the world is not allowed to be judge in his
own cause; I know some who, in order not to fall into this self-love,
have been perfectly unjust out of opposition. The sure way of losing a
just cause has been to get it recommended to these men by their near
relatives.

Justice and truth are two such subtle points, that our tools are too
blunt to touch them accurately. If they reach the point, they either
crush it, or lean all round, more on the false than on the true.