The air signs are gemini, libra and aquarius. The three qualities are cardinal, fixed and mutable. Four signs share a quality. Cardinal signs are aries, libra, cancer and capricorn. Fixed signs are taurus, scorpio, leo and aquarius.
Mutable signs are gemini, sagittarius, virgo and pisces.
Lastly, the twelve signs are alternately positive and negative, beginning with the first sign, aries, which is positive. These are known as the polarities. The pattern of elements and qualities in the astrological signs is constant every third sign has the same element. Every fourth sign has the same quality. So, each of the twelve signs represents a different combination of element and quality.