The fatal tendency of mankind to leave off thinking about a thing when it is no longer doubtful is the cause of half their errors.
Interpretation
People tend to stop thinking critically about a subject once they believe they understand it, leading to mistakes.
In this quote, John Stuart Mill highlights the human inclination to cease deep thought and critical analysis once something becomes clear or accepted as true. This tendency can lead to complacency and errors in judgment, suggesting that ongoing questioning and reflection are necessary to avoid misconceptions and ensure clarity in understanding.
In practice
During a debate on education policies, one might use this quote to emphasize the importance of continuous evaluation.
The peculiar evil of silencing the expression of an opinion is, that it is robbing the human race; posterity as well as the existing generation; those who dissent from the opinion, still more than those who hold it. If the opinion is right, they are deprived of the opportunity of exchanging error for truth: if wrong, they lose, what is almost as great a benefit, the clearer perception and livelier impression of truth, produced by its collision with error.
As for charity, it is a matter in which the immediate effect on the persons directly concerned, and the ultimate consequence to the general good, are apt to be at complete war with one another.
To think that because those who wield power in society wield in the end that of government, therefore it is of no use to attempt to influence the constitution of the government by acting on opinion, is to forget that opinion is itself one of the greatest active social forces. One person with a belief is a social power equal to ninety-nine who have only interests.
There should be perfect freedom, legal and social, to do the action and stand the consequences. It would be a great misunderstanding of this doctrine to suppose that it is one of selfish indifference, which pretends that human beings have no business with each other's conduct in life, and that they should not concern themselves about the well-doing or well-being of one another, unless their own interest is involved.
Political Economy, in truth, has never pretended to give advice to mankind with no lights but its own; though people who knew nothing but political economy (and therefore knew it ill) have taken upon themselves to advise, and could only do so by such lights as they had.
Marriage is the only actual bondage known to our law. There remain no legal slaves, except the mistress of every house.
It's sometimes too easy to point fingers when circumstances dramatically go awry, but as an addict, I'm ultimately responsible for my own decisions, no matter how benign or tragic the consequences.
I do not want to be admired. I want to give, to be given, and solitude in which to unfold my possessions.
Trust no one, not even the finest saint who ever walked this earth, ignore him, if he hinders your sight of Jesus Christ.
The really good idea is always traceable back quite a long way, often to a not very good idea which sparked off another idea that was only slightly better, which somebody else misunderstood in such a way that they then said something which was really rather interesting.
I want God to play in my bloodstream the way sunlight amuses itself on the water.
If someone's ungrateful and you tell him he's ungrateful, okay, you've called him a name. You haven't solved anything.
Subscribe for the occasional hand-picked quote. No noise.