天台教学における二鳥倶遊について

抄録

Kācilindi（ka） 迦隣提 and cakravāka 鴛鴦 are names of birds of the same species. In English, these birds are called the Mandarin duck. They are described in the Mahāparinirvāṇa mahāsūtra as a metaphor called the Two Birds Metaphor 二鳥喩. Since kācilindi and cakravāka indicate the same bird, these two names are inseparable or equal. The sūtra uses the metaphor to demonstrate the fundamental truth that impermanence 無常 and permanence 常 are inseparable.

Based on this metaphor, Zhiyi 智顗 （538-597）, the founder of Chinese Tiantai, uses the phrase èr niǎo jù yóu 二鳥倶遊 to describe cháng wúcháng bùdé xiānglí 常無常不得相離 in his commentary on the Vimalakīrtinirdeśa, Weimo jing wenshu 維摩経文疏.

Incidentally, the Mandarin duck is known as a creature whose males and females always move together. Therefore, yuānyang 鴛鴦, the Chinese translation of cakravāka, includes the meanings of both male and female Mandarin ducks. But given the nature of this creature, it is unclear what the two birds are meant to represent for Zhiyi. In other words, it can be understood that Zhiyi expected not kācilindi and cakravāka but a male bird and a female when he referred to èr niǎo jù yóu.

To conclude, Guanding 灌頂 （561-632）, the second patriarch of the Tiantai and a pupil of Zhiyi, understood the two birds as male and female in his commentary on the Mahāparinirvāṇa mahāsūtra, Da banniepan jing shu 大般涅槃経疏. The understanding of Guanding differs from that of the sūtra itself, since the sutra describes kācilindi and cakravāka as two different birds. This change can be pointed out as one aspect of the scholastic transition from Zhiyi to Guanding.