Sam Harris quotes that I wrote down without getting the source. They are from the lessons and interviews in the Waking Up App which I love as I am delving deeper into mindfulness. Also recommended is the Making Sense Podcast.
…to recognize how consciousness is prior to thinking, reacting, or trying to change your experience, in any way at all, can be the most important thing you ever learn to do.
…a choice between noticing what arises in your mind, and not noticing…
When you are suffering you are lost in thought.