of the very same action may alter if we determinately confine ourselves
to the favourable aspect in which it may be viewed, keeping the contrary
side entirely out of sight.

As soon as this has been carried to the utmost, you must further (that
my experiment may be fairly tried) endeavour to throw yourself, in
imagination, not only into the position, but also into the natural and
acquired mental and moral perceptions of the person whose action you are
taking into your consideration. For this purpose you must often
imagine--natural dimness of perception, absence of acute sensibility,
indifference to wounding the feelings of others from mere carelessness
and want of reflective powers, little natural conscientiousness, an
entire absence of the taste or the power of metaphysical examination
into the effect produced by our actions. All these natural deficiencies,
you must further consider, may in this case be increased by a totally
neglected education,--first, by the want of parental discipline, and
afterwards of that more important self-education which few people have
sufficient strength of character to subject themselves to. Lastly, I
would have you consider especially the moral atmosphere in which they
have habitually breathed: according to the nature of this the mental
health varies as certainly as the physical strength varies in a bracing
or relaxing air. A strong bodily constitution may resist longer, and
finally be less affected by a deleterious atmosphere than a weak or
diseased frame; and so it is with the mental constitution. Minds
insensibly imbibe the tone of the atmosphere in which they most
frequently dwell; and though natural loftiness of character and natural
conscientiousness may for a very long period resist such influences, it
cannot be expected that inferior natures will be able to do so.

You are then to consider whether the habits of mind and conversation