Sandai Soron (三代相論)
Sandai Soron is a general name for a religious conflict in the Soto sect, which started in 1267 and lasted for about 50 years. It is regarded as a conflict between conservatives, who complied with the relic teachings of the sect's founder Dogen, and reformists, who attached more importance to propagation among the common people.
Occasionally, the period in which Gikai was appointed as the third chief priest of Eihei-ji Temple through his resign is regarded as the first period, the period in which Gikai was reappointed and again resigned is regarded as the second period, and the period in which a conflict arose in the later years as to whether to accept Gikai as the third head priest is regarded as the third period.
The first period
When Dogen died in September 1253, his disciple Koun Ejo succeeded to the position of chief priest of Eihei-ji Temple and became the second head priest of the Soto sect.
There were two groups in the Soto sect at that time: a group of direct disciples of Dogen after he came back from the Sung (dynasty), and a group of priests who converted to the Soto sect from the Nihon Daruma sect as a group after Dogen established Kosho-ji Temple at Fukakusa, Kyoto. Ejo belonged to the group of the Nihon Daruma sect, but since he was courteous and sincere he endeavored to achieve harmony and mediate the two groups; consequently, the conflict between the groups didn't rise to the surface.
Ejo, on one hand, faithfully complied with the relic of Dogen, but on the other hand he constructed the cathedral and established the rules of Eihei-ji Temple, sending Gikai TETTSU, his priestly nephew, to Sung to collect research and documents in 1262.
When Ejo decided to resign in 1267, a conflict arose as to whether Gikai, who planned to proceed with maintenance and restructuring, or Gien, who regarded the compliance with the relic as the primal duty, should succeed the position as head priest. As a result, Gikai became as the third chief priest of Eihei-ji Temple and the third head priest of the Soto sect. However, repulse against the rapid restructuring arose gradually, and those who did not practice the activities decided by Gikai appeared one after another, compelling Gikai to resign in the period of March to April of 1272.
The second period
After Gikai resigned, Ejo was reappointed, but he died in 1280. The problem of choosing a successor arose again, but there was no right person in the conservative group so, based on the wish of Ejo, Gikai was reappointed in Eihei-ji Temple.
Gikai tried to reconcile with the opposing group by changing the rules he had made to the old ones and so on, but since the conflict seemed to deepen, in 1287, after seven years had passed, he left Eihei-ji Temple and moved to Daijo-ji Temple in Kaga Province. On that occasion, many disciples who followed Gikai moved to Daijo-ji Temple also, resulting in the division of Dogen's group into Eihei-ji Temple and Daijo-ji Temple.
The third period
After Gikai left, Gien was appointed as the chief priest of Eihei-ji Temple, but since the temple was impoverished due to the conflict and because Gien couldn't earn the trust of the Hatano clan, the Kaiki (patron of a temple in its founding) of the Soto clan, the power of the temple rapidly diminished. Eventually Gien resigned too, and according to "Nihon Tojo rentoroku," he secluded himself in a small temple and never showed up again.
It is believed that there was no chief priest in Eihei-ji Temple for a while, but when Gien died and Giun succeeded the position in November or December of 1314, a dispute arose as to whether Gikai should be counted as one of the successive chief priests of Eihei-ji Temple. This dispute was settled by accepting Gikai as the third chief priest, but the honorary title of 'Chuko' (restorer) that Gikai had retained until then was withdrawn. There is even a theory that it was late in the Edo period that Gikai was officially counted as one of the successive chief priests of Eihei-ji Temple.
Because Gikai and Gien both belonged to the group of the Nihon Daruma sect, the conflict shouldn't be regarded merely as a conflict between the group under the direct lineage of Dogen and the group of the Nihon Daruma sect. However, since Gien pointed out that Gikai had redundantly transformed shiho (to inherit the dharma from a priest master) from Ejo into the Zen of Dogen and the teaching of the Nihon Daruma sect when he was criticizing Gikai, fundamentally the characteristic as a conflict between the two groups can be seen.