The psychic gift
The aspect of undecile, like the septile, is generated by a periodic rational number (360/11 = 32.72 … = 32° 43′ 38.172″). The related aspects on the 11th harmonic are biundecile (65° 27′ 16″), triundecile (98° 10′ 54″), quadriundecile (130° 54′ 32″) and quinqueundecile (163° 38′ 10″). The angular width of the undecile is very close to that of the semi-sextile (30°); if you want to use it, the orbit’s tolerance is, therefore, very narrow (one degree at maximum).
According to the texts dealing with the subject, the meaning that emerges is that of an aspect that explores the correlations with spiritual evolution, similar to the periodic aspect of the septile. Unlike the latter, which defines the fatal outcomes (in the sense of the destiny towards which we feel called), the undecile would indicate more the psychic gift, the subtle dynamic that belongs to us and of which we are often unaware. The symbolic similarity on the zodiacal level is that of Aquarius (eleventh sign): the inspiration that arises from the pouring of celestial waters which fertilise and illuminate the sense of earthly experience.
Numerologically, the number 11 is reduced to 2 by theosophical addition (1 + 1). This time on a different level, it re-proposes the binary relationship between the male and female aspects of existence, which must finally integrate to synthesise heavenly and earthly. This justifies the attribution of undecile to the psychic gift, made possible only when one becomes permeable to higher influences. Furthermore, the sign of Aquarius, as a double sign – to represent the celestial and terrestrial waters – also fulfils the task of uniting the high and the low, the subtle and the dense, through the grace of inspiration.
However, there is also a negative side of undecile, which partly derives from being – as for the septile – a periodic aspect. His tendency towards a stable vibration does not always result in suggestions from above; if the conscience is not yet sufficiently prepared, the resulting visions can be disturbing because they are not understandable or not communicable; in the latter case, the individual would undergo the isolation due to experiences in which others cannot participate. According to astrologers interested in studying higher harmonics, the eleventh harmonic, in its critical aspects, would be at the origin of some of the so-called neurodivergences, such as, for example, autism spectrum disorders.