Astrological sign of a sign are together sufficient to define it, they can be grouped to indicate their symbolism. The first four signs, Aries, Taurus, Gemini and Cancer, form the group of personal signs. The next four signs, Leo, Virgo, Libra and Scorpio form the group of interpersonal signs. The last four signs of the zodiac, Sagittarius, Capricorn, Aquarius and Pisces, form the group of transpersonal signs. Dane Rudhyar presented the tropical zodiac primary factors, used in the curriculum of the RASA School of Astrology. The tropical zodiac is the zodiac of seasonal factors as opposed to the sidereal zodiac (constellation factors).
Zodiac Killer be a suspect. Retired police handwriting expert Lloyd Cunningham, who worked the Zodiac case for decades, added "they gave me banana boxes full of Allen's writing, and none of his writing even came close to the Zodiac. Nor did DNA extracted from the envelopes (on the Zodiac letters) come close to Arthur Leigh Allen." While police often use document examiners during investigations, court rulings on the scientific validity of handwriting analysis have been mixed to negative. In 2007, a man named Dennis Kaufman claimed that his stepfather Jack Tarrance was the Zodiac. Kaufman turned several items over to the FBI