Majjhima Nikaya 5:154
SUJATOyampi taṁ diṭṭhaṁ sutaṁ mutaṁ viññātaṁ pattaṁ pariyesitaṁ, anuvicaritaṁ manasā, tampi ‘netaṁ mama, nesohamasmi, na meso attā’ti samanupassati;
whatever is seen, heard, thought, known, attained, sought, and explored by the mind like this: ‘This is not mine, I am not this, this is not my self.’