“Rules necessary for definitions. Not to leave any terms at all obscure or ambiguous without definition; Not to employ in definitions any but terms perfectly known or already explained.”

The Art of Persuasion

The Art of Persuasion

The Divine Commodity: Discovering A Faith Beyond Consumer Christianity (2009, Zondervan)

Source: Onward Industry!, 1931, p. 31

Part I : Ambiguity and Freedom
The Ethics of Ambiguity (1947)
Context: The failure described in Being and Nothingness is definitive, but it is also ambiguous. Man, Sartre tells us, is “a being who makes himself a lack of being in order that there might be being.” That means, first of all, that his passion is not inflicted upon him from without. He chooses it. It is his very being and, as such, does not imply the idea of unhappiness. If this choice is considered as useless, it is because there exists no absolute value before the passion of man, outside of it, in relation to which one might distinguish the useless from the useful. The word “useful” has not yet received a meaning on the level of description where Being and Nothingness is situated. It can be defined only in the human world established by man’s projects and the ends he sets up. In the original helplessness from which man surges up, nothing is useful, nothing is useless. It must therefore be understood that the passion to which man has acquiesced finds no external justification. No outside appeal, no objective necessity permits of its being called useful. It has no reason to will itself. But this does not mean that it can not justify itself, that it can not give itself reasons for being that it does not have. And indeed Sartre tells us that man makes himself this lack of being in order that there might be being. The term in order that clearly indicates an intentionality. It is not in vain that man nullifies being. Thanks to him, being is disclosed and he desires this disclosure. There is an original type of attachment to being which is not the relationship “wanting to be” but rather “wanting to disclose being.” Now, here there is not failure, but rather success.

The Relation of the State to the Invididual (1890)
Context: Anarchists, whose mission in the world is the abolition of aggression and all the evils that result therefrom, perceived that, to be understood, they must attach some definite and avowed significance to the terms which they are obliged to employ, and especially to the words "State" and "government." Seeking, then, the elements common to all the institutions to which the name "State" has been applied, they have found them two in number: first, aggression; second, the assumption of sole authority over a given area and all within it, exercised generally for the double purpose of more complete oppression of its subjects and extension of its boundaries.

XII, 95
On the Improvement of the Understanding (1662)
Context: A definition, if it is to be called perfect, must explain the inmost essence of a thing, and must take care not to substitute for this any of its properties. In order to illustrate my meaning, without taking an example which would seem to show a desire to expose other people's errors, I will choose the case of something abstract, the definition of which is of little moment. Such is a circle. If a circle be defined as a figure, such that all straight lines drawn from the center to the circumference are equal, every one can see that such a definition does not in the least explain the essence of a circle, but solely one of its properties. Though, as I have said, this is of no importance in the case of figures and other abstractions, it is of great importance in the case of physical beings and realities, for the properties of things are not understood so long as their essences are unknown. If the latter be passed over, there is necessarily a perversion of the succession of ideas which should reflect the succession of nature, and we go far astray from our object.

Source: 1930s-1951, The Blue Book (c. 1931–1935; published 1965), p. 26

What Is Life? (1944)