I present myself as a traditional astrologer these days, at least in spirit if not yet in full-fledged practice. So I don’t use the trans-Saturnian planets for much beyond generational insights. That means I don’t see Uranus, Neptune and Pluto as sign rulers or dispositors, or as partaking of the other essential dignities, or even as major players in the architecture of personality. I did so for the better part of forty years as a psychological astrologer weaned on the likes of Marc Edmund Jones, Dane Rudhyar and Robert Hand, but I’ve seen enough compelling testimony (I won’t call it “evidence”) from respected traditional astrologers to believe that the interpretive body of knowledge behind the “modern” planets is, putting it kindly, still “provisional” at best (although some critics might even say it’s “half-baked”). I won’t go so far as to insist that Uranus has no affinity for Aquarius, nor Neptune for Pisces and Pluto for Scorpio, but I don’t see them as rulers or even co-rulers (although “higher octave” of the traditional rulers has a nice ring to it), and some of the character-based attributions seem highly suspect.
As far as depth of psychological analysis, the system of temperaments employed by traditional astrologers is perfectly adequate to delineate four basic character types according to the classical elements of Empedocles: Choleric, or Fiery; Sanguine, or Airy; Phlegmatic, or Watery; and Melancholic, or Earthy. The related qualities of warmth, dryness, coolness and wetness were anthropomorphized to equate them to human nature in various proportions, offering sufficient complexity to be accurate enough for all practical purposes. There is, of course, nothing Jungian about it, but I’m not sure that’s a bad thing.
The classical rulership model is quite symmetrical and elegant. Starting at Cancer, the Moon’s sign, and moving clockwise around the zodiac, you encounter signs ruled by Mercury, Venus, Mars, Jupiter and Saturn. Beginning at Leo, the Sun’s sign, and proceeding counter-clockwise, you meet signs ruled by Mercury, Venus, Mars, Jupiter and Saturn. Thus, each of the planets except the “lights” rules two signs, and the only concession to irregularity is that the scheme results in two Saturn-ruled signs back-to-back. Those who insist on mucking up the beauty of the system with more planets and asteroids seem to be following the “Everest Principle:” we have to use them because they’re there. (Besides, how would we sell books and work the lecture circuit if we don’t?)
I vividly recall attending a lecture by Rob Hand at the Belmont Library in Massachusetts in the early 1980s. At one point, he proclaimed loudly and confidently, “There is absolutely nothing superficial about Pluto!” By the ’90s he had moved on to Project Hindsight and taken up the seven planets of classical astrology as his main focus. There are a couple of modern books on traditional astrology that make an excellent case for returning to the old ways. The first, Understanding the Birth Chart: A Comprehensive Guide to Classical Interpretation by Kevin Burk, has more of a “cook-book” style that is highly readable; he does treat with Uranus, Neptune, Pluto and Chiron, but only as generational factors. On the Heavenly Spheres by Helena Avelar and Luis Ribeiro is more of a technical read but is jam-packed with information. For anyone interested in a traditional overview with a healthy measure of practical guidance, these two will take you a long way. (If you can afford it, pick up the non-facsimile edition of William Lilly’s three-volume Christian Astrology while you’re at it.) Of course, I would never toss my copy of Sakoian and Acker’s The Astrologer’s Handbook, Rob Hand’s Planets in Transit or Rex Bills’ The Rulership Book, but I now take much of their content with a large grain of salt.