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There is rich symbolism in the four directions: right, left, up, and down. There are meanings associated with each, which apply to handwriting, be it letters, words, body writing, or envelopes.
It is likely that the predominance of the right hand among people explains the association of force with the right as the side of action. The somatic sensations of laterality are undoubtedly the source of the multiple symbolic meanings that have been attached to the duality of right and left, and that have found expression in all cultures and in all times. They are reflected in law and ritual, in magic and superstition, in language and literature; and they are perpetuated not only in folklore but also in modern everyday uses.
In the cultural tradition of the Chinese, the mystical opposites yang and yin, which in ancient times simply meant light and dark, have finally come to encompass all associative aspects of a fundamental polarity. Yang is the masculine principle, the sky, the creative, the active, the positive, the straight, the undivided, the favorable; yin is the feminine principle, the earth, the receptive, the submissive, the negative, the twisted, the divided, the unfavorable.
In early Hindu and Egyptian religious cults, the right side of the body symbolized strength and aggressive action; the left side, feeling and receptivity. The goddess Isis was represented with a sword in her right hand and a flower in her left. Primitive tribes interpret the right and the left in the same animistic and symbolic terms: the male body is conceived of as having masculine characteristics on the right side and feminine characteristics on the left. A Swiss cultural anthropologist, JJ Bachofen, has described an interesting inversion of this symbolism in certain matriarchal societies.
The antithesis of right and left extends beyond all physical implications to the domain of moral, social, and religious values as well. In the Old Testament story, King Solomon places his mother in the seat of honor at his right hand; and early Christian theologians designated the right side of heaven as the upper sphere, while the left side was given a lower evaluation. The Gospel of Matthew, explaining how the good will be separated from the bad on Judgment Day, says: “And he will put the sheep on his right hand, and the goats on his left.”
It is not surprising that the right and the left developed similar meanings on mundane levels too, and that these have acquired an endless increase in popular attitudes no less than superstitions. Starting off on the wrong foot brings luck; a ringing in the right ear is a good omen, and a twitch in the right eye is believed to bring praise and money. Thus we find that the “honourable” right and the “wicked” left become the “lucky” right and the “unlucky” left.
These left and right associations provide information to handwriting analysts.