“Enlightenment is man's emergence from his self-incurred immaturity.”
What is Enlightenment? (1784)
Context: Enlightenment is man’s leaving his self-caused immaturity. Immaturity is the incapacity to use one's intelligence without the guidance of another.
Context: Enlightenment is man’s leaving his self-caused immaturity. Immaturity is the incapacity to use one's intelligence without the guidance of another. Such immaturity is self-caused if it is not caused by lack of intelligence, but by lack of determination and courage to use one's intelligence without being guided by another. Sapere Aude! Have the courage to use your own intelligence! is therefore the motto of the enlightenment.
Original
Aufklärung ist der Ausgang des Menschen aus seiner selbstverschuldeten Unmündigkeit. Unmündigkeit ist das Unvermögen, sich seines Verstandes ohne Leitung eines anderen zu bedienen. Selbstverschuldet ist diese Unmündigkeit, wenn die Ursache derselben nicht am Mangel des Verstandes, sondern der Entschließung und des Mutes liegt, sich seiner ohne Leitung eines anderen zu bedienen. Sapere aude! Habe Mut, dich deines eigenen Verstandes zu bedienen! ist also der Wahlspruch der Aufklärung.
Beantwortung der Frage: Was ist Aufklärung?
Beantwortung der Frage: Was ist Aufklärung? (1784)
Variant: Aufklärung ist der Ausgang des Menschen aus seiner selbst verschuldeten Unmündigkeit. Unmündigkeit ist das Unvermögen, sich seines Verstandes ohne Leitung eines anderen zu bedienen. Selbstverschuldet ist diese Unmündigkeit, wenn die Ursache derselben nicht am Mangel des Verstandes, sondern der Entschließung und des Mutes liegt, sich seiner ohne Leitung eines anderen zu bedienen. Sapere aude! Habe Mut dich deines eigenen Verstandes zu bedienen! ist also der Wahlspruch der Aufklärung.
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Immanuel Kant 200
German philosopher 1724–1804Related quotes

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Source: Advanced Systems Thinking, Engineering and Management (2003), p. 24

Comparable to remarks of William Masters, in "Two Sex Researchers on the Firing Line" LIFE magazine (24 June 1966), p. 49: "Science by itself has no moral dimension. But it does seek to establish truth. And upon this truth morality can be built."
Variants:
Science does not have a moral dimension. It is like a knife. If you give it to a surgeon or a murderer, each will use it differently.
As quoted in Futurehype: The Myths of Technology Change (2009) by Robert B. Seidensticker
Science does not have a moral dimension. It is like a knife. If you give it to a surgeon or a murderer, each will use it differently. Should the knife have not been developed?
As quoted in Science & Society (2012) by Peter Daempfle, Ch. 6, p. 97<!-- also in Good Science, Bad Science, Pseudoscience, and Just Plain Bunk: How to Tell the Difference (2013) by Peter Daempfle, Ch. 9, p. 166 -->
Responsible Scientific Investigation and Application (1976)
Context: One of the most disconcerting issues of our time lies in the fact that modern science, along with miracle drugs and communications satellites, has also produced nuclear bombs. What makes it even worse, science has utterly failed to provide an answer on how to cope with them. As a result, science and scientists have often been blamed for the desperate dilemma in which mankind finds itself today.
Science, all by itself, has no moral dimension. The same poison-containing drug which cures when taken in small doses, may kill when taken in excess. The same nuclear chain reaction that produces badly needed electrical energy when harnessed in a reactor, may kill thousands when abruptly released in an atomic bomb. Thus it does not make sense to ask a biochemist or a nuclear physicist whether his research in the field of toxic substances or nuclear processes is good or bad for mankind. In most cases the scientist will be fully aware of the possibility of an abuse of his discoveries, but aside from his innate scientific curiosity he will be motivated by a deep-seated hope and belief that something of value for his fellow man may emerge from his labors.
The same applies to technology, through which most advances in the natural sciences are put to practical use.