Suññatalokasutta
Atha kho āyasmā ānando …pe… bhagavantaṁ etadavoca: “‘suñño loko, suñño loko’ti, bhante, vuccati. Kittāvatā nu kho, bhante, suñño lokoti vuccatī”ti? “Yasmā ca kho, ānanda, suññaṁ attena vā attaniyena vā tasmā suñño lokoti vuccati. Kiñca, ānanda, suññaṁ attena vā attaniyena vā? Cakkhu kho, ānanda, suññaṁ attena vā attaniyena vā. Rūpā suññā attena vā attaniyena vā, cakkhuviññāṇaṁ suññaṁ attena vā attaniyena vā, cakkhusamphasso suñño attena vā attaniyena vā …pe… yampidaṁ manosamphassapaccayā uppajjati vedayitaṁ sukhaṁ vā dukkhaṁ vā adukkhamasukhaṁ vā tampi suññaṁ attena vā attaniyena vā. Yasmā ca kho, ānanda, suññaṁ attena vā attaniyena vā, tasmā suñño lokoti vuccatī”ti.
The World is Empty
And then Venerable Ānanda … said to the Buddha: “Sir, they say that ‘the world is empty’. What does the saying ‘the world is empty’ refer to?” “Ānanda, they say that ‘the world is empty’ because it’s empty of self or what belongs to self. And what is empty of self or what belongs to self? The eye, sights, eye consciousness, and eye contact are empty of self or what belongs to self. … The pleasant, painful, or neutral feeling that arises dependent on mind contact is also empty of self or what belongs to self. They say that ‘the world is empty’ because it’s empty of self or what belongs to self.”