Mindfulness is a state ...

Mindfulness is a state wherein one is totally aware in any situation and so always able to respond appropriately. Yet one is aware of being aware. Mindlessness, on the other hand, or "no-mindness" as it has been called, is a condition of such complete absorption that there is not vestige of self-awareness.
 Philip Kapleau

Quotes from the same author

The uniqueness of zazen lies in this: that the mind is freed from bondage to all thought forms, visions, objects, and imaginings, however sacred or elevating, and brought to a state of absolute emptiness, from which alone it may one day perceive its own true nature, or the nature of the universe.
 Philip Kapleau
To be reborn hourly and daily in this life, we need to die — to give of ourselves wholly to the demands of the moment, so that we utterly "disappear." Thoughts of past, present, or future, of life and death, of this world and the next, are transcended in the superabundance of the now. Time and timelessness coalesce: this is the moment of eternity.
 Philip Kapleau
Die while alive And be thoroughly dead. Then do what you will, All is good.
 Philip Kapleau
Zen Master Dogen has pointed out that anxiety, when accepted, is the driving force to enlightenment in that it lays bare the human dilemma at the same time that it ignites our desire to break out of it.
 Philip Kapleau
To put the flesh of an animal into one's belly makes one an accessory after the fact of its slaughter, simply because if cows, pigs, sheep, fowl, and fish, to mention the most common, were not eaten they would not be killed.
 Philip Kapleau