knowledge of _other men_.

Every _mental_ characteristic of your prospect about which you need to
know has _physical indications that can be perceived, and translated
into certain knowledge of details of his character_. You have studied
the co-relation of _your_ mind and body in mutual development. You may
be sure that similar processes of development have produced like effects
in the case of the man you have come to see. You know exactly how to
grow particular qualities within yourself, by using your muscles to
develop corresponding mind centers and vice versa. You can read another
man's mind by observing _his_ muscle structure and muscle action, and by
then interpreting the mental significance of what you perceive.

[Sidenote: Men are Alike At Heart, But Differ in Mind]

To repeat and emphasize again what already has been said about knowing
the _heart_ of another man--you need but look into your own breast to
find there the finest basic characteristics of the human heart in
general. As Kipling wrote, "The Colonel's lady and Judy O'Grady are
sisters under their skins." All men are fundamentally alike at the
bottoms of their hearts, however much they may differ in the individual
traits they have grafted upon their common root of human nature.

So when you are sizing up your prospect, you should comprehend that _the
most effective way to get to his heart is through such an appeal as
would reach the heart of every man_. Know your own heart surely, then,
in order to be certain of knowing his. All human hearts respond
similarly to manifestations of courage, nobility, love, faith, honor,
and the like. We laugh and cry at the same humor and pathos. Our
_feelings_ are closely akin. We differ from one another only in our
_minds_. Our individual, acquired habits of thought affect but the
_degrees_ of our several heart responses to the gamut of fundamental
emotional appeals.

[Sidenote: Exhaustive Prolonged Analysis Unnecessary]

Knowledge of another man, then, involves first, comprehension that he is
_like_ every other man in his _emotions_, and _unlike_ all other men in
the way he _thinks_. To a trained observer his habits of thought are
clearly indicated by his muscle structure and muscle action. Exhaustive
prolonged analysis is unnecessary. You can learn to read quickly the
mental significance of the comparatively small number of details of
muscle structure and action that constitute a fairly complete index to
his char