Indeed the reasoned criticism of a prevailing belief is a service to the proponents of that belief; if they are incapable of defending it, they are well advised to abandon it. This self-questioning and error-correcting aspect of the scientific method is its most striking property.
He soon felt that the fulfillment of his desires gave him only one grain of the mountain of happiness he had expected. This fulfillment showed him the eternal error men make in imagining that their happiness depends on the realization of their desires.
The only thing that one really knows about human nature is that it changes. Change is the one quality we can predicate of it. The systems that fail are those that rely on the permanency of human nature, and not on its growth and development. The error of Louis XIV was that he thought human nature would always be the same. The result of his error was the French Revolution. It was an admirable result.
Truths ... are too often considered as so true, that they lose all the power of truth, and lie bed-ridden in the dormitory of the soul, side by side with the most despised and exploded errors.
A collection of errors does not make a truth: quality cannot stem from quantity – a value is not a weight. The reasons of the majority cannot be taken as good reasons.
Understand that for every rule which I have mentioned from the Quran, the Devil has one to match it, which he puts beside the proper rule to cause error.
There is only one inborn erroneous notion ... that we exist in order to be happy ... So long as we persist in this inborn error ... the world seems to us full of contradictions. For at every step, in great things and small, we are bound to experience that the world and life are certainly not arranged for the purpose of maintaining a happy existence ... hence the countenances of almost all elderly persons wear the expression of ... disappointment.
There is an error common to both oligarchies and to democracies: in the latter the demagogues, when the multitude are above the law, are always cutting the city in two by quarrels with the rich, whereas they should always profess to be maintaining their cause; just as in oligarchies the oligarchs should profess to maintain the cause of the people, . .