If my happiness at this moment consists largely in reviewing happy memories and expectations, I am but dimly aware of this present. I shall still be dimly aware of the present when the good things that I have been expecting come to pass. For I shall have formed a habit of looking behind and ahead, making it difficult for me to attend to the here and now. If, then, my awareness of the past and future makes me less aware of the present, I must begin to wonder whether I am actually living in the real world.
— The Wisdom of Insecurity by Alan Watts
(vulgo, Lo zen di ogni istante: uno dei modi per impedire che siano i costanti borbottii della mente a godersi la vita al posto nostro)