It would be better for the uninstructed run-of-the-mill person to hold to the body composed of the four great elements, rather than the mind, as the self. Why is that? Because this body composed of the four great elements is seen standing for a year, two years, three, four, five, ten, twenty, thirty, forty, fifty, a hundred years or more. But what's called 'mind,' 'intellect,' or 'consciousness' by day and by night arises as one thing and ceases as another. Just as a monkey, swinging through a forest wilderness, grabs a branch. Letting go of it, it grabs another branch. Letting go of that, it grabs another one. Letting go of that, it grabs another one. In the same way, what's called 'mind,' 'intellect,' or 'consciousness' by day and by night arises as one thing and ceases as another.
Assutavā Sutta: Uninstructed (1)