When we look at the ordinary mind, what stands out is its complete unreliability.

One day we feel one way, the next another; this month we are completely convinced, but next month we have grave doubts.

We reach the heights of joy, then we fall to the depths of misery; we imagine wonderful accomplishments, then plunge into self-doubt; we awaken to the beauty of life, then we go to sleep again.

In the face of such changeability, there can be no real security, no guarantees as to where our mind will go next—nothing is trustworthy. 

Mind over Matter