The very beginning of our modern right-handedness goes back, indeed, to the most primitive savagery.  Why did one hand ever come to be different in use and function from another?  The answer is, because man, in spite of all appearances to the contrary, is really one-sided.  Externally, indeed, his congenital one-sidedness doesn’t show:  but it shows internally.  We all of us know, in spite of Sganarelle’s assertion to the contrary, that the apex of the heart inclines to the left side, and that the liver and other internal organs show a generous disregard for strict and formal symmetry.  In this irregular distribution of those human organs which polite society agrees to ignore, we get the clue to the irregularity of right and left in the human arm, and finally even the particular direction of the printed letters now before you.

For primitive man did not belong to polite society.  His manners were strikingly deficient in that repose which stamps the caste of Vere de Vere.  When primitive man felt the tender passion steal over his soul, he lay in wait in the hush for the Phyllis or Daphne whose charms had inspired his heart with young desire; and when she passed his hiding-place, in maiden meditation, fancy free, he felled her with a club, caught her tight by the hair of her head, and dragged her off in triumph to his cave or his rock-shelter. (Marriage by capture, the learned call this simple mode of primeval courtship.) When he found some Strephon or Damoetas rival him in the affections of the dusky sex, he and that rival fought the matter out like two bulls in a field; and the victor and his Phyllis supped that evening off the roasted remains of the vanquished suitor.  I don’t say these habits and manners were pretty; but they were the custom of the time, and there’s no good denying them.

Now, Primitive Man, being thus by nature a fighting animal, fought for the most part at first with his great canine teeth, his nails, and his fists; till in process of time he added to these early and natural weapons the further persuasions of a club or shillelagh.  He also fought, as Darwin has very conclusively shown, in the main for the possession of the ladies of his kind, against other members of his own sex and species.  And if you fight, you soon learn to protect the most exposed and vulnerable portion of your body; or, if you don’t, natural selection manages it for you, by killing you off as an immediate consequence.  To the boxer, wrestler, or hand-to-hand combatant, that most vulnerable portion is undoubtedly the heart.  A hard blow, well delivered on the left breast, will easily kill, or at any rate stun, even a very strong man.  Hence, from a very early period, men have used the right hand to fight with, and have employed the left arm chiefly to cover the heart and to parry a blow aimed at that specially vulnerable region.  And when weapons of offence and defence supersede mere fists and teeth, it is the right hand that grasps the spear or sword, while the left holds over the heart for defence the shield or buckler.