Pennyroyal (Mentha pulegium) is a pungent, creeping mint whose very name derives from the Latin pulegium, a reference to its ancient use against fleas (pulex). In the herbal tradition, however, pennyroyal is most notorious as a powerful emmenogogue—an agent that stimulates menstrual flow. The phrase "Jupiter, Pennyroyal, & all emmenogogues" thus binds the herb and its entire class of uterine stimulants to the expansive, regulatory, and often dangerous authority of the planet Jupiter. The connection is not one of gentle rulership but of forceful expulsion: Jupiter's sphere governs growth, abundance, and the release of pressure, and emmenogogues enact that principle in the most literal physiological sense.

Position on the Tree of Life

This correspondence occupies Path 13, the link between Kether and Tiphareth on the Tree of Life. Path 13 is assigned to the Hebrew letter Gimel and the Moon, yet here the vegetable drug column places Jupiter—traditionally a Sephirotic planet of Chesed—at this lunar path. The paradox is deliberate: the Moon rules the tides of the womb, while Jupiter rules the expansive, purgative force that drives those tides into action. The emmenogogue thus becomes a lunar-Jovian hybrid, a substance that uses Jupiter's explosive abundance to clear the lunar channel.

Astrological and Planetary Correspondence

Jupiter is the Greater Benefic, the planet of expansion, mercy, and release. In the language of herbal magic, Jupiter governs the liver, the blood, and the principle of elimination through the large intestine and the uterus. Emmenogogues—pennyroyal, tansy, rue, savin, and ergot—are all Jovian in their action: they force the body to expel what it holds, whether that is retained menses, a fetus, or a stagnant humor. The association is not gentle; it is the Jupiter of thunderbolts and sudden liberation, not the Jupiter of feasts and philosophy.

Historical Context

Pennyroyal has been known since antiquity. The Greek physician Dioscorides (1st century CE) prescribed it for uterine obstructions, and Pliny the Elder noted its power to provoke menstruation and abortion. In medieval and Renaissance herbals, pennyroyal appears consistently as a woman's herb—dangerous, effective, and often condemned by ecclesiastical authorities for its abortifacient use. The English herbalist John Gerard (1597) warned that pennyroyal "provoketh the termes, and bringeth away the birth," a phrase that captures both its medical and its moral peril. By the 19th century, pennyroyal oil was a staple of folk medicine and a notorious tool for self-induced abortion, its toxicity well known but its availability unmatched. The herb's essential oil, pulegone, is hepatotoxic and can be fatal in doses only slightly above the therapeutic range—a fact that underscores the Jovian principle of excess: what expands too far destroys.

The category "all emmenogogues" in the 777 system is deliberately broad. It includes not only pennyroyal but also ergot (a fungus of rye, used to induce labor and control postpartum hemorrhage), savin (juniper, a violent purgative and abortifacient), and rue (a bitter herb of ancient ritual use). Each of these shares the Jovian signature of forced release, and each appears in the historical record as both medicine and poison, regulated by the state and the church precisely because of their power over fertility.

In the 777 Table

At Path 13 of the Vegetable Drugs column, the entry "Jupiter, Pennyroyal, & all emmenogogues" stands as a single compressed formula. It does not list every emmenogogue but names the planetary ruler and the archetypal herb, leaving the rest as an implied class. The neighboring paths reinforce the theme: Path 17 gives "Ergot and ecbolics" (substances that expel the fetus), and Path 28 gives "All diuretics" (agents of urinary release). The entire column is a map of bodily and spiritual purgation, and at Path 13, Jupiter sits at the lunar gate, commanding the blood to flow.