Mahāvagga

Suttapiṭaka · Saṁyuttanikāya · Nidānavaggasaṁyutta · Vol. 16 · Section 232

[232] Bhikkhus, just as a monkey, roaming in a forest, in a great wood, grabs hold of a branch; letting that go, it grabs hold of another; letting that go, it grabs hold of another; letting that go, it grabs hold of another — even so, bhikkhus, that which is called 'mind (citta)', and also 'mentality (mano)', and also 'consciousness (viññāṇa)' arises as one thing and ceases as another by night and by day.

English translation from the Pali (Siam Raṭṭha edition) — under review, not for citation.