The opinions that are held with passion are always those for which no good ground exists; indeed the passion is the measure of the holders lack of rational conviction. Opinions in politics and religion are almost always held passionately.

When anaesthetics were invented they were thought to be wicked as being an attempt to thwart God's will. Insanity was thought to be due to diabolic possession, and it was believed that demons inhabiting a madman could be driven out by inflicting pain upon him, and so making them uncomfortable. In pursuit of this opinion, lunatics were treated for years on end with systematic and conscientious brutality.

It is a natural propensity to attribute misfortune to someone's malignity.

I once saw a photograph of a large herd of wild elephants in Central Africa Seeing an airplane for the first time, and all in a state of wild collective terror... As, however, there were no journalists among them, the terror died down when the airplane was out of sight.

William James describes a man who got the experience from laughing-gas; whenever he was under its influence, he knew the secret of the universe, but when he came to, he had forgotten it. At last, with immense effort, he wrote down the secret before the vision had faded. When completely recovered, he rushed to see what he had written. It was 'A smell of petroleum prevails throughout'.

We believe, first and foremost, what makes us feel that we are fine fellows.

Moreover, the attitude that one ought to believe such and such a proposition, independently of the question whether there is evidence in its favor, is an attitude which produces hostility to evidence and causes us to close our minds to every fact that does not suit our prejudices.