A happy life must be to a great extent a quiet life, for it is only in an atmosphere of quiet that true joy dare live.
A life without adventure is likely to be unsatisfying, but a life in which adventure is allowed to take whatever form it will is sure to be short.
A process which led from the amoeba to man appeared to the philosophers to be obviously a progress though whether the amoeba would agree with this opinion is not known.
A sense of duty is useful in work but offensive in personal relations. People wish to be liked, not to be endured with patient resignation.
A truer image of the world, I think, is obtained by picturing things as entering into the stream of time from an eternal world outside, than from a view which regards time as the devouring tyrant of all that is.
Admiration of the proletariat, like that of dams, power stations, and aeroplanes, is part of the ideology of the machine age.
Advocates of capitalism are very apt to appeal to the sacred principles of liberty, which are embodied in one maxim: The fortunate must not be restrained in the exercise of tyranny over the unfortunate.
Against my will, in the course of my travels, the belief that everything worth knowing was known at Cambridge gradually wore off. In this respect my travels were very useful to me.
Almost everything that distinguishes the modern world from earlier centuries is attributable to science, which achieved its most spectacular triumphs in the seventeenth century.
Aristotle could have avoided the mistake of thinking that women have fewer teeth than men, by the simple device of asking Mrs. Aristotle to keep her mouth open while he counted.
Aristotle maintained that women have fewer teeth than men; although he was twice married, it never occurred to him to verify this statement by examining his wives' mouths.