The longing to behold this pre-established harmony [of phenomena and theoretical principles] is the source of the inexhaustible patience and perseverance with which Planck has devoted himself ... The state of mind which enables a man to do work of this kind is akin to that of the religious worshiper or the lover; the daily effort comes from no deliberate intention or program, but straight from the heart.

I owe as much of my success to an uncompromising obstinacy as to any original ideas.

The power of imagination is the ultimate creative power.. no doubt about that. While knowledge defines all we currently know and understand.. imagination points to all we might yet discover and create. Imagination is more important than knowledge. Your imagination is your preview of life's coming attractions

I have never looked upon ease and happiness as ends in themselves - this critical basis I call the ideal of a pigsty. The ideals that have lighted my way, and time after time have given me new courage to face life cheerfully, have been Kindness, Beauty, and Truth. Without the sense of kinship with men of like mind, without the occupation with the objective world, the eternally unattainable in the field of art and scientific endeavors, life would have seemed empty to me. The trite objects of human efforts - possessions, outward success, luxury - have always seemed to me contemptible.

When a man, after long years of searching, chances upon a thought which discloses something of the beauty of this mysterious universe, he should not therefore be personally celebrated. He is already sufficiently paid by his experience of seeking and finding.

But the personality that finally emerges is largely formed by the environment in which a man happens to find himself during his development, by the structure of the society in which he grows up, by the tradition of that society, and by its appraisal of particular types of behavior.

Compassionate people are geniuses in the art of living, more necessary to the dignity, security, and joy of humanity than the discoverers of knowledge.