The eager and often inconsiderate appeals of reformers and revolutionists are indispensable to counterbalance the inertia and fossilism marking so large a part of human institutions. – Walt Whitman, Democratic Vistas, 1871

We need — and should encourage and honour — not only discoverers of facts hitherto unknown but explorers of ideas and rethinkers of values. – Walter Moberly, The Crisis in the University

The reasonable man adapts himself to the world; the unreasonable one persists in trying to adapt the world to himself. Therefore all progress depends on the unreasonable man. – G.B. Shaw, Man and Superman, 1903