Nichiren Daishonin, the Buddha of the Latter Day of the Law, declared: “In judging the relative merit of Buddhist doctrines, I, Nichiren, believe that the best standards are those of reason and documentary proof. And even more valuable than reason and documentary proof is the proof of actual fact” (“Three Tripitaka Masters Pray for Rain,” The Writings of Nichiren Daishonin, vol. 1, p. 599).
These three proofs—namely, documentary proof, theoretical proof and actual proof—form the standard for discerning the truth, validity and superiority not only of various Buddhist teachings, but also of theories and teachings in the general sphere of philosophy, science and so on.
He [Nichiren Daishonin] then declares that, while documentary and doctrinal evidence is important in considering the efficacy of a Buddhist teaching, far more important is “the proof of actual fact,” that is, the power of a religion to positively affect the human condition.
World Tribune Dec 13, 2019 p2