"Know thyself" was the advice dispensed by the oracle of Delphi, the sanctuary dedicated to the Roman goddess Venus.
That same advice is symbolized by the secular symbol for "woman," the circle sitting atop a cross. The "handmirror of Venus" is the ancient astrological symbol of the planet Venus. In the mirror, woman is meant to see herself and the representation of her being and beauty.
Venus, the daughter of Jupiter and Dione, is the goddess of love, queen of pleasure and mother of the Roman people. She was married to Vulcan and had four children, the most recognizable of whom are Cupid and Hymen. She also took as her lover the Roman god of war, Mars. Astute readers may recognize this association as responsible for the modern dictum that "Men are from Mars, Women are from Venus."
Double interlocking female symbols have typically been used to denote lesbianism, but may also be taken as a representation of the sisterhood of women. Some lesbian feminists of the '70s used three interlocking symbols to represent a rejection of male standards of monogamy.
Modern astrologers state that Venus is the ruling planet of pleasure, interpersonal relations and all things aesthetic. Beauty, whatever its form, and the appreciation thereof, is ruled by Venus. Venus is intensely feminine and decrees revelry in an extremely sensual, though not sexual world.