This term, with the meaning in question, occurs perhaps only once in the Canon, namely in Kath. (s. Guide 83). Whether it is found also somewhere in the Com. , I am unable to say.
”Suchness”, designates the firmly fixed nature (bha^va) of all things whatever. The only passage in the Canon where the word occurs in this sense, is found in Kath. 186 (s. Guide, p. 83). On the Maha^yana term tathata^, s. Suzuki, Awakening of Faith, p. 53f. (App.).