Ignorance is the necessary condition, i do not say of happiness, but of life itself. If we knew everything, we could not endure existence a single hour. The sentiments that make it sweet to us, or at any rate tolerable, spring from a falsehood, and are fed on illusions.
If, like God, a man possessed the truth, the sole and perfect truth, and once let it escape out of his hands, the world would be annihilated there and then, and the universe melt away instantly like a shadow.

The evil that is in the world always comes of ignorance, and good intentions may do as much harm as malevolence, if they lack understanding. On the whole men are more good than bad; that, however, isn't the real point. But they are more or less ignorant, and it is this that we call vice or virtue; the most incorrigible vice being that of an ignorance which fancies it knows everything and therefore claims for itself the right to kill. There can be no true goodness, nor true love, without the utmost clear-sightedness.

Every other knowledge is harmful to him who does not have knowledge of goodness.

Morality negates life.

Man's knowledge, save before his fellow man,
Is ignorance—his widest wisdom folly.

The audacity of the man would have seemed sublime if she had felt sure that he knew the difference between good and evil, between a lie and the truth; but the more she saw of him, the surer she was that his courage was mere moral paralysis, and that he talked about virtue and vice as a man who is colour-blind talks about red and green; he did not see them as she saw them; if left to choose for himself he would have nothing to guide him. Was it politics that had caused this atrophy of the moral senses by disuse? Meanwhile, here she sat face to face with a moral lunatic.

The impurity of ignorance is in none so manifest as in the devout; for they act on their ignorance, and fill themselves and others with miserable scruples and hard thoughts of God, and are as apt to call good evil as other men are to call evil good.

Man is arrogant in proportion to his ignorance.

The evil in the world comes almost always from ignorance, and goodwill can cause as much damage as ill-will if it is not enlightened. People are more often good than bad, though in fact that is not the question. But they are more or less ignorant and this is what one calls vice or virtue, the most appalling vice being the ignorance that thinks it knows everything and which consequently authorizes itself to kill. The murderer's soul is blind, and there is no true goodness or fine love without the greatest possible degree of clear-sightedness.

This is why, as soon as this condition fails to appear, the imprescriptible love of others also disappears. The other is now just another person, a person as people are – hypocrites, liars, ambitious, sinful, egotistical, blind, fighting ferociously for their own advantage and prestige, no less combative toward others who oppose their projects and desires. Forgetful of their veritable condition and the other’s veritable condition, they behave toward themselves and others as mere people. Then the whole edifying morality that wishes to found itself on the mere person, on the rights of man, discovers its emptiness, its prescriptions are flouted, and the world is given over to horror and sordid exploitation, to massacres and genocides. It is not by chance that in the twentieth century the disappearance of “religious” morality has given rise not to a new morality, a “secular morality,” albeit a morality without any definite foundation, but to the downfall of any morality and to the terrifying and yet daily spectacle of that downfall.

Without man and his potential for moral progress, the whole of reality would be a mere wilderness, a thing in vain, and have no final purpose.

The evil that is in the world almost always comes from ignorance, and good intentions may do as much harm as malevolence if they lack understanding.

An ignorant man, who is not fool enough to meddle with his clock, is however sufficiently confident to think he can safely take to pieces, and put together at his pleasure, a moral machine of another guise, importance and complexity, composed of far other wheels, and springs, and balances, and counteracting and co-operating powers. Men little think how immorally they act in rashly meddling with what they do not understand. Their delusive good intention is no sort of excuse for their presumption. They who truly mean well must be fearful of acting ill.

where ignorance is bliss, ‘tis folly to be wise.