Ptolemy in Heian Japan?

As part of my ongoing PhD research here in Japan I picked up a copy of Mikkyō Senseijutsu – Sukuyō-dō to Indo Senseijutsu 密教占星術ー宿曜道とインド占星術 [Esoteric Buddhist Astrology – Sukuyō-dō and Indian Astrology] by scholar Yano Michio 矢野道雄 (1944-). It is essentially an introduction and analysis of the history behind Indian astrology in the East Asian cultural sphere, specifically with respect to the Xiuyao-jing 宿曜經 (in Japanese Sukuyō-kyō), which was used in esoteric Buddhism in China and Japan.

As I introduced in an earlier post (see here), the text was translated by the eminent Vajra Master Amoghavajra 不空 in 759 and then later revised in 764 by his lay disciple Yang Jingfeng 楊景風 under his master's guidance. This laid the groundwork for the later astrological tradition of Sukuyō-dō 宿曜道 in Japan, which emerged around the middle of the eleventh century and flourished for a few centuries, perhaps until the Muromachi period (1337-1573). The tradition never died out, though it appears it was often kept secret, at least judging from one twentieth century Japanese account I've surveyed. The Kōyasan scholar Morita Ryūsen 森田龍僊 inherited such a living tradition and wrote, from his emic perspective, a work entitled Mikkyō Sensei Hō 密教占星法 [Esoteric Buddhist Astrology Methods] in 1941.1 While such a work is useful in many respects, it was not written from a scientific perspective. Aside from his work there was not a great deal of concentrated academic work done on the subject until Yano's research, which is objective and critical (there are many modern popular works on Sukuyō-dō).

One very interesting theory put forth by Yano is that, quite possibly, the Sukuyō-dō tradition was early on in possession of a Classical Chinese translation of the Tetrabiblos by Greco-Egyptian astrologer Ptolemy (90-168).2 To begin with, he points out that in 865 the Japanese monk Shū'ei 宗叡 (809-884) brought back with him, among other texts, the following title:


Tori-isshi-kyō, One Part, Five Scrolls

The title here is provided in the Sino-Japanese (on-yomi) reading. In modern Mandarin it would be Duli-yusi-jing. The Sino-Japanese readings, originally preserved from Chinese pronunciations from the Tang period (618-907), better reflect the original title name than Mandarin, so I will use the former here.

Yano proposes that the title here actually stands for Ptolemy's name and presumably would be his work the Tetrabiblos (the Four Books). It is not impossible to imagine that the work could have been translated into Chinese, especially considering the flow of Hellenic sciences eastward through the efforts of Nestorianism. It was translated into Syrian in the seventh century and Persian in the late eighth century.

Ptolemy in Greek is Ptolemaios. In languages like Syrian, however, the vowels are not represented, hence it would be rendered something like this if it were in Roman:


The P could easily be dropped, likewise for some reason the M. The result would be:


Compare this with the Chinese:


To-Ri-Itsu-Shi (Sino-Japanese)
Du-Li-Yu-Si (Mandarin)

This argument is further advanced by texts listed in later catalogs The New Book of Tang 新唐書 (a revised history of the Tang, compiled in 1060) lists this work with the following remark:


In the Zhenyuan period (785-805) transmitted from western India by To-ri adept Li Miqian and translated by Qu Gong.

Following this another work is listed:


Chen Fu, Isshi Shi-mon Kyō, One Scroll

Chen Fu here appears to be a personal name, either the compiler or translator. The title literally reads Isshi Four Gates Classic. One will note the Isshi here is the same as the Tori-isshi-kyō above. The “four gates” here could possibly be a predictable Chinese rendering of Tetrabiblos (Four Books). If Yano is correct, then the Chinese is supposed to say the Tetrabiblos of Ptolemaios. However, Yano is only cautiously stating this as a tentative theory.

This text or some version of it was in fact brought to Japan in 865 and readily utilized by astrologers of the later Sukuyō tradition. We know this because in extant horoscopes (Jpn. Sukuyō Kanmon 宿曜勘文) there are citations of the text. The text itself, however, is no longer extant. However, the fragments that do exist clearly demonstrate a Hellenic model of horoscopes. For instance, consider the following citations from a horoscope from the year 1152:

Saturn is in Jupiter's palace [Pisces] 
Jupiter is in the Moon's palace [Cancer]  
Saturn and Jupiter are 120 degrees apart [trine]. 
Mars and the Sun are 120 degrees apart [trine]. 
Venus and Mercury are in the same zodiac mansion [Aquarius].

These are concepts stemming from Hellenic astrology (Ptolemy's or otherwise), especially the concept of aspect (here trine or in Chinese san he 三合). However, they are not mentioned in the horoscope methods provided by Amoghavajra, who was versed in Indian models of astrology. It is unclear whether he was aware of such concepts, but nevertheless the main text in question was evidently Hellenic in origin and did have an impact in both China and Japan, though it is almost entirely forgotten aside from a few scholars today.

The aforementioned New Book of Tang does state it came from western India, though it has been long known that there was a great deal of Hellenic influence in Indian astral sciences from early on. The scholar David Edwin Pingree (1933-2005) after a lifetime of study divided Indian astrology into four categories based on the origins of the material:

I. Vedic (c.1000-400 BCE). II. Babylonian (400 BCE-200 CE): VedāṅgajyotiṣaIII. Greco-Babylonian (c200-400): YavanajātakaIV. Greek (c400-1600): ĀryabhaṭīyaV. Islamic (c1600-1800).

The third text on the list the Yavanajātaka is literally the Jātaka of the Greeks. Modern scholarship has furthermore traced Hellenic influences in chronologically dated Indian materials related to astral science. Hence, while the Chinese might have understood the text in question above as having come from western India, in reality it might have been just as well an import there from further west originally.

It should come as no surprise that such a Hellenic model was introduced in the Tang dynasty, which has been understood as a “cosmopolitan empire”.3 Buddhists especially made great efforts to adapt imported Indian models to native Chinese models, though as Pankenier remarks it did not have a lasting effect in China:

On the whole, however, these syncretic efforts had almost no influence on long-established Chinese astrological theory, especially given the drastic decline of Buddhism following the Tang Dynasty suppression in the mid ninth century and the subsequent resurgence of Neo-Confucianism. Assimilation was also hindered by the difficulty of rendering foreign concepts and terminology into Chinese, which was often accomplished by means of bizarre or idiosyncratic transliterations.4

Still, in conclusion we might say that it is remarkable should Yano be correct and Ptolemy's Tetrabiblos was in fact translated into Chinese around the year 800, later influencing the development of Sukuyō astrology in Japan starting from the Heian period in the eleventh century. If anything, it just demonstrates how much hybridization occurred in this period: Vedic, Buddhist, Hellenic and Chinese models were brought together and even in the furthest frontier of East Asia – Japan – one can see elements of Hellenic astrology active in the same aristocratic world which gave birth to literature like the Tale of Genji.5

It is always interesting uncovering these subtle strands of history which span great time and space.



1 Morita Ryūsen 森田龍僊. Mikkyō Sensei Hō 密教占星法. Kōyasan: Kōyasan Daigaku Shuppan-bu, 1941.

2 See Yano Michio 矢野道雄, Mikkyō Senseijutsu – Sukuyō-dō to Indo Senseijutsu 密教占星術ー宿曜道とインド占星術 (Tokyo, Japan: Tōyō Shoin, 2013), 160-164.

3 For example, Mark Edward Lewis, China's Cosmopolitan Empire The Tang Dynasty (Cambridge, MA: The Belknap Press of Harvard University Press, 2009).

4 David Pankenier, Astrology and Cosmology in Early China Conforming Earth to Heaven (Cambridge University Press, 2013), 9-10.

5 There are also a lot of Buddhist elements in the work. See the following by me: Buddhism and the Tale of Genji.