Immanuel Kant, Idea for a Universal History with a Cosmopolitan Purpose, under the fifth proposition:
Man, who is otherwise so enamoured with unrestrained freedom, is forced to enter this state of restriction by sheer necessity. And this is indeed the most stringent of all forms of necessity, for it is imposed by men upon themselves, in that their inclinations make it impossible for them to exist side by side for long in a state of wild freedom. But once enclosed within a precinct like that of civil union, the same inclinations have the most beneficial effect. In the same way, trees in a forest, by seeking to deprive each other of air and sunlight, compel each other to find these by upward growth, so that they grow beautiful and straight–whereas those which put out branches at will, in freedom and in isolation from others, grow stunted, bent and twisted.
John Stuart Mill, On Liberty, Chapter II, “Of the liberty of thought and discussion”
Socrates was put to death, but the socratic philosophy rose like the sun in heaven, and spread its illumination overt the whole intellectual firmament. Christians were cast to the lions, but the Christian church grew up a stately and spreading tree, overtopping the older and less vigorous growths, and stifling them by its shade. Our merely social intolerance kills no one, roots out no opinions, but induces men to disguise them or to abstain from any active effort for their diffusion.
Far from missing the forest for the trees, there is a world of disagreement buried in this wood.