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Glenn Perry - Planets as Faculties & Functions

AstroPsychology is a reformulation of astrology in terms of psychological concepts and practices. Although psychological astrology received its initial impetus from Carl Jung’s analytical psychology, more recent attempts include the assimilation of ideas from psychodynamic theory, general systems theory, cognitive behavioral psychology, and various other models and perspectives. Perhaps the defining attribute of a psychological approach to astrology is its focus on integrating the birth chart and, thus, supporting the human potential for growth and change. As such, AstroPsychology can be conceptualized as a personality theory, developmental model, and diagnostic/prognostic tool.

A core tenet of AstroPsychology is that planets symbolize functions that are oriented toward satisfying the needs of the signs they rule. Signs are motives; planets are their active agents. Another way of saying this is that a planet symbolizes a psychological faculty, which can be defined as an inherent power or ability to perform functions. Planetary functions are the normal, proper, or characteristic actions of that planet; thus, for example, Mars symbolizes the functions of asserting, starting, fighting, competing, and surviving. While early humans experienced planetary archetypes as messages from gods originating outside of their own minds, today we recognize archetypes as the core feelings, needs, and values that constitute our inner life.

Again, planetary functions are motivated by the need(s) of the sign that planet rules. This implies that motivation and function are as inseparable as a rocket and its fuel tank. Each sign-planet pairing can be regarded as a system. When we talk about the body, we refer to specific systems such as the cardiovascular system, the gastrointestinal system, and the endocrine system. Likewise, there are psychological systems. Aries-Mars rules the competitive/assertion system, Taurus-Venus the security/stability system, and Capricorn-Saturn the control/mastery system. A sign-planet is a motivational system because it entails an interaction between two components of the psyche: sign and planet. As needs, signs motivate their ruling planets to perform specific functions, and these functions involve appropriate actions that serve the underlying motive.

Abraham Maslow (1968) proposed that human beings are born with an essential nature that is analogous with physical structure. Just so in astrology, psychological functions are analogous to their biological corollaries. The functions of digestion and elimination, for example, parallel corresponding psychological processes ruled by Virgo-Mercury and Scorpio-Pluto. Just as we digest food, so we digest information, breaking it down into useful parts and assimilating it into our cognitive structure. We also eliminate on a psychological level, as when we experience catharsis, abreaction, or overcome a destructive mental habit—all of which are ruled by the Scorpio-Pluto system. This is why biological and corollary psychological functions are ruled by the same sign-planet system.

Whereas the Virgo-Mercury system governs the intestines, gastrointestinal system, and overall food metabolism, it also governs psychological process of analyzing and utilizing information in the service of competence. In other words, Virgo is about the metabolizing of information—a clear corollary to the process of digestion on a biological level. Likewise, biological and psychological processes of elimination are ruled by Scorpio-Pluto. On a biological level, Scorpio-Pluto governs the sexual/generative organs, which include the bladder, prostate gland, testicles, colon, and rectum. Note that these organ systems are involved in processes of ejection and elimination; ovulation and menstruation in the female and ejaculation in the male. Psychologically, Scorpio-Pluto rules sexuality and tends to be penetrating, erotic, and regenerative by its very nature. It also involves psycho-eliminative processes such as the purging of destructive emotions and habits. These two examples—Virgo-Mercury and Scorpio-Pluto—should suffice to illustrate how a sign-planet system is analogous to a biological organ, and symbolizes a specific type of action that is in the service of a psychological need, or motive.

Just as the need of a sign can be inferred from behaviors that characterize that sign, so a planet’s functions can be inferred from actions that characterize its nature. This is simply a matter of inductive reasoning. By observing characteristic actions of a planet, one can discern where the actions are leading to—in short, the purpose of the behavior. An action is any behavior that is goal-directed, or done for a reason. If one observes that Neptune is implicated in spiritual strivings, compassion for suffering, redemptive love, charity, psi abilities, fantasy, and dreams, then the functions of Neptune would have to account for all actions classified as Neptunian.

If we call Neptune the Transcendent Faculty, this may suffice, for spiritual strivings are in the service of transcending the separate self-sense and uniting with a higher consciousness. Concern for the less fortunate, charity, and redemptive love require one to transcend self-interest and act to relieve the suffering of others. Psi abilities involve cognitive capacities that transcend rational intellect and sensory experience, while fantasy and dreams involve the perception of ideals and possibilities that transcend everyday, material reality. While no single word does justice to the diverse forms this archetypal process takes, Transcendent Faculty is as good a term as any. It may be that the best name for a planetary faculty is simply the planet itself—in this case, the faculty of Neptune.

Any characteristic action of a planet can be converted from a verb into a noun, which gives us a name for that function. Recall that planetary functions are the normal, proper, or characteristic actions of that planet. For example, Neptune symbolizes the verbs to imagine, to empathize, and to intuit. By converting these verbs into nouns we get three functions of Neptune: imagination, empathy, and intuition. Each term captures one facet of a complex, psychological faculty. Of course, there are other functions of Neptune beyond these three.

Again, functions are always in the service of needs. For every need represented by a sign, there is a planetary function devoted to the fulfillment of that need. Signs and planets form verb-noun pairs, as it were, the planet being the active agent (verb) of the sign-need (noun) over which it rules. Saturn, for instance, is the planet that rules Capricorn. The need of Capricorn can be described as the drive for perfection in material form—or, put simply, the need for order, structure and control. Saturn, as the verb form and active agent of Capricorn, fulfills its needs by ordering, structuring, and controlling within the behavioral environment. Hence, Saturn represents the functions of order, structure, and control. In this regard, every planet symbolizes a particular kind of activity. Planets are actors and each one acts in a different way.

In an actual chart, Saturn would be in a particular sign. Let us say, for instance, that Saturn is in Gemini. Thus, we have the syntax of an astrological sentence: the need of Capricorn (noun) is fulfilled by Saturn (verb) in a Gemini manner (adverb). In short, the need for order is fulfilled by achieving intellectually. Saturn in Gemini represents the drive for perfection through the ordering of mental constructs. If Saturn is highlighted in the natal chart (e.g., conjunct the Sun), we might have an individual, for instance, with an obsessive need to structure language into a logical system. Perhaps he might write a book on linguistics or devise a theory of syntax. The Gemini sign placement merely suggests how Saturn fulfills its Capricorn-need and what some possible outcomes might be.

The point here is that needs symbolized by signs provide the motivation that triggers functions represented by planets. How and whether those functions satisfy their motivating needs is indicated by a host of additional factors including the planet’s sign and house position and its aspects to other planets. The degree to which a planet can satisfy its sign-need is a measure of that planet’s functionality (or dysfunctionality). This is a topic of considerable complexity, however, so we will stop here for now. Interested readers might explore the books below for more information.



  • Maslow, A. (1968). Toward a psychology of being. Princeton, NJ: Van Nostrand.
  • Perry, G. (2012). An Introduction to AstroPsychology. Haddam Neck, CT: AAP Press.
  • Perry, G. (2012). Depth Analysis of the Natal Chart. Haddam Neck, CT: AAP Press.


Glenn Perry, Ph.D., is an astrologer and licensed psychotherapist in Connecticut, USA. He received his doctorate in psychology from Saybrook Institute. In addition to private practice, Dr. Perry is director of the Academy of AstroPsychology, an online school that offers courses and training in psychological astrology. Glenn has written eight books, including An Introduction to Astro Psychology, and serves as a Board member and qualitative research advisor for ISAR. He lectures internationally on the application of astrology to the fields of counseling and psychotherapy.