What You Don't Understand

"The first thing to learn in intercourse with others is non-interference with their own peculiar ways of being happy, provided those ways do not assume to interfere by violence with ours. No one has insight into all the ideals. No one should presume to judge them off-hand. The pretension to dogmatize about them in each other is the root of most human injustices and cruelties, and the trait in human character most likely to make the angels weep.

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"We have unquestionably a great cloud-bank of ancestral blindness weighing down upon us, only transiently riven here and there by fitful revelations of the truth. It is vain to hope for this state of things to alter much. Our inner secrets must remain for the most part impenetrable by others, for beings as essentially practical as we are are necessarily short of sight. But, if we cannot gain much positive insight into one another, cannot we at least use our sense of our own blindness to make us more cautious in going over the dark places? Cannot we escape some of those hideous ancestral intolerances and cruelties, and positive reversals of the truth?"

William James, from Talks to Teachers on Psychology, etc. as excerpted in The Philosophy of William James, pp. 339-41.