Economics is a science of thinking in terms of models joined to the art of choosing models which are relevant to the contemporary world. It is compelled to be this, because, unlike the typical natural science, the material to which it is applied is, in too many respects, not homogeneous through time. The object of a model is to segregate the semi-permanent or relatively constant factors from those which are transitory or fluctuating so as to develop a logical way of thinking about the latter, and of understanding the time sequences to which they give rise in particular cases. Good economists are scarce because the gift for using "vigilant observation" to choose good models, although it does not require a highly specialised intellectual technique, appears to be a very rare one.
John Maynard KeynesRelated topics
art choosing choose constant contemporary economics fluctuating gift good intellectual latter material model natural object observation particular rare rise science segregate technique thinking time typical understanding unlike using way world respectsRelated quotes
As conceived in this book, economics is the science of rational choice in a world─our world─in which resources are limited in relation to human wants. The task of economics, so defined, is to explore the implications of assuming that man is a rational maximizer of his ends in life, his satisfactions─what we shall call his "self-interest.” Rational maximization should not be confused with conscious calculation. Economics is not a thoery about consciousness. Behavior is rational when it conforms to the model of rational choice, whatever the state of mind of the chooser.(...) Nor is perfect rationality assumed; rational-choice thoery allows us to assume that rationality is "bounded” because of human cognitive limitations, although another way to think of those limitations is as costs of absorbing and using information.
Richard Posner
In a certain sense all knowledge is inductive. We can only learn the laws and relations of things in nature by observing those things. But the knowledge gained from the senses is knowledge only of particular facts, and we require some process of reasoning by which we may collect out of the facts the laws obeyed by them. Experience gives us the materials of knowledge: induction digests those materials, and yields us general knowledge. When we possess such knowledge, in the form of general propositions and natural laws, we can usefully apply the reverse process of deduction to ascertain the exact information required at any moment. In its ultimate foundation, then, all knowledge is inductive-in the sense that it is derived by a certain inductive reasoning from the facts of experience.
William Stanley Jevons
Only the actual conception of the divine nature changes according to the different ideas of perfection which prevail in particular ages and nations. The gods of the remoter ages of Greece and Rome, and those worshipped by our own earliest forefathers, were simply ideals of bodily strength and prowess. As the idea of sensuous beauty arose and gradually became refined, the sensuous personification of beauty was exalted to the throne of deity; and hence arose what we might call the religion of art. When men ascended from the sensuous to the purely spiritual, from the beautiful to the good and true, the sum of all moral and intellectual perfection became the object of their adoration, and religion became the province of philosophy.
Wilhelm von Humboldt
Returning to the moon is an important step for our space program. Establishing an extended human presence on the moon could vastly reduce the costs of further space exploration, making possible ever more ambitious missions. Lifting heavy spacecraft and fuel out of the Earth's gravity is expensive. Spacecraft assembled and provisioned on the moon could escape its far lower gravity using far less energy, and thus, far less cost. Also, the moon is home to abundant resources. Its soil contains raw materials that might be harvested and processed into rocket fuel or breathable air. We can use our time on the moon to develop and test new approaches and technologies and systems that will allow us to function in other, more challenging environments. The moon is a logical step toward further progress and achievement.
George W. Bush
According to Aristotle then excellence of character and intelligence cannot be separated. Here Aristotle expresses a view characteristically at odds with that dominant in the modern world. The modern view is expressed at one level in such banalities as ‘Be good, sweet maid, and let who will be clever' and at another in such profundities as Kant's distinction between the good will, the possession of which alone is both necessary and sufficient for moral worth, and what he took to be a quite distinct natural gift, that of knowing how to apply general rules to particular cases, a gift the lack of which is called stupidity. So for Kant one can be both good and stupid; but for Aristotle stupidity of a certain kind precludes goodness.
Alasdair MacIntyre
