A sane man among the insane always appears so.
There is a beautiful story by Khalil Gibran which I have always loved:
There was an ancient town ruled by a well-loved king and queen. Into the only well — except that for the sole use of the king and queen and their prime minister — a magician throws a potion. The magician declares, “Whoever drinks the water will go mad.” Obviously, except for the king and queen and the prime minister, the whole town goes mad. They had to drink from that well, and they all went mad. Except for the king, the queen and the prime minister, they all go mad.
All the mad townspeople are gathered around the palace shouting against the king and saying, “The king has gone mad. We don’t want a mad king.”
The king asked his chief minister what to do. The minister must have been a wise man, not like politicians today, a man of insight, not elected but chosen by the wise. He said, “I will keep the crowd happy for a time. You run to the town’s well and drink deeply. Drink deeply. Get drunk on it. Then come back and all will be right.”
The king soon returns, but entering through the front door naked, singing, dancing… singing songs of ecstasy he dances with the crowd. The king’s dance convinces the crowd of his sanity. They declare him sane. They recrown him. They rejoice. They celebrate his return to sanity.
Story told by Osho