As you know, the 12 Zodiac Signs all have personalities. A further way to explore commonalities between the signs is to examine their underlying "Qualities": Cardinal, Fixed, and Mutable. These Quadruplicities, groups of four Signs 90 degrees away from each other that reflect a person's attitudes in life and the way they approach projects.

The four Cardinal signs are Aries, Cancer, Libra, and Capricorn. Thy're the ones found at East, North, West, and South - the First, Fourth, Seventh, and Tenth Houses. Each one has a strong character. They have initiative and motivation, they get things moving, but they're not necesasarily good at follow-through.

The four Fixed signs are Taurus, Leo, Scorpio, and Aquarius, the Second, Fifth, Eighth, and Eleventh Houses. Because they're stable and reliable, they're the ones who see projects through to completion. However, they can also be stubborn and inflexible.

The four Mutable signs are Gemini, Virgo, Sagittarius, and Pisces, the Third, Sixth, Ninth, and Twelfth Houses. These people are happy to fill assigned roles, and are adaptable to changing circumstances. Their weakness is that they can be wishy-washy.