The Buddha, who lived some 600 years BCE, taught that life, as we live it, is necessarily unharmonious because of the selfish, possessive attitude we adopt towards it. In Sanskrit this attitude is called trishna (often mistranslated “desire”), and though there is no one word for it in English, it may be understood as the craving to resist change, to “save our own skins” at all costs, to possess those whom we love; in fact, to hold on to life “like grim death.” And that particular phrase has its moral. If anything that lives and moves is held, it dies just like a plucked flower. Egotism is a fierce holding on to oneself; it is building oneself up in a haughty stronghold, refusing to join in the play of life, refusing to accept the eternal laws of change of movement to which all are subject. But that refusal can only be illusion. Whether we like it or not, change comes, and the greater the resistance, the greater the pain. Buddhism perceives the beauty of change, for life is like music in this: if any note or phrase is held for longer than its appointed time, the melody is lost. Thus Buddhism may be summed up in two phrases: “Let go!” and “Walk on!” Drop the craving for self, for permanence, for particular circumstances, and go straight ahead with the movement of life.
From Become What You Are by Alan Watts, pages 59–60