[り, ri] (n) (1) reason; principle; logic; (2) { Buddh } (See 事・じ) general principle (as opposed to individual concrete phenomenon); (3) (in neo-Confucianism) the underlying principles of the cosmos; (P)#3287
[つきとめる, tsukitomeru] (v1, vt) to determine (esp. a culprit or underlying cause); to pin down; to make sure; to locate; to identify; to find out; to ascertain