All significant truths are private truths. As they become public they cease to become truths; they become facts, or at best, part of the public character; or at worst, catchwords.
History is full of people who out of fear, or ignorance, or lust for power has destroyed knowledge of immeasurable value which truly belongs to us all. We must not let it happen again.
But it was ever thus, all through my life: whenever I have diverged from custom and principle and uttered a truth, the rule has been that the hearer hadn't strength of mind enough to believe it.