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Key Concepts of Jean-Paul Sartre's Philosophy


Jean-Paul Sartre was a 20th-century French philosopher, novelist, and playwright. Sartre was heavily influenced by German philosophers Friedrich Nietzsche, Karl Marx, and Martin Heidegger and became the leading 20th-century figure of what would be called "Existentialism," both as a philosopher and as a writer of fiction. Sartre studied at the Sorbonne, where he met Simone de Beauvoir. Beauvoir would become Sartre's lifelong friend and sometimes lover. She was a huge influence on his philosophical and literary works and offered pointed criticism of some of Sartre's philosophy to illustrate places she thought that he had gone wrong. As a result the two philosophers are usually taught side by side in classrooms, and it is not fully known how many of the ideas that have been credited to Sartre are actually a collaboration between the two.


Existentialism was not a term coined by Sartre or any other philosopher but one that the media attached to a certain movement of philosophy and literature that began to develop out of the 19th century. The philosophers Schopenhauer, Kierkegaard, and Nietzsche as well as the novelists Franz Kafka and Fyodor Dostoevsky were all concerned with combating nihilism in the modern world while at the same time rejecting the search for an objective truth about the experience of being human and instead trying to find a justification for meaning from the experiences of being human. In the twentieth century writers such as Heidegger, Sartre, and Albert Camus were labeled existentialists. Heidegger and Camus rejected this label but Sartre decided to embrace it, feeling that if he took the label as his own philosophy he would then be allowed to define it.

One of the key beliefs of existentialism, according to Sartre, is that existence proceeds essence. What this means is that human beings are defined by their actions. There is no essential human nature. Being human is an act of constantly becoming something through the choices that we make. In this way human beings are constantly evolving and do not finish this journey until they are dead. Sartre borrowed the idea of angst from Heidegger and insisted that the main human motivation is the fear of death.

As an atheist it was Sartre's contention that death was a state of nothingness but while there were plenty of philosophers linked to existentialism who were atheists, there also were Christians labeled existentialists like Dostoevsky, Kierkegaard and Sartre contemporary Karl Jaspers as well as the Jewish philosopher Martin Buber. What both the religious and atheistic existentialists had in common was that they considered the truth of religion to be irrelevant to its value. Whether or not God existed it was up to humans as individuals to find their own meaning in life wheresoever they could find it.

While Nietzsche rejected the idea of free will, stating that men are determined by their basic drives to become who they are, Sartre took a radically different approach to free will. He thought that since human beings were defined by their actions only that this meant that human beings were completely free. Every action that a human being takes is his and his alone and so the responsibility of being completely in control of ones own actions caused dread. This existential dread was the price that we paid for our freedom and would form the basis of what would become Sartre's ethics.


Like many philosopher before him, Sartre's ideas about ethics directly proceeded from his ideas about free will. The conclusion that Sartre comes to sounds remarkable similar to the ethics of Immanuel Kant, but the key difference is that while Kant attempted to drive justification of his ethics from objective reason, Sartre was basing his work on the human experience and the way human actions define human beings. Sartre concluded that since humans are solely responsible for their actions and this causes dread, that to act in anyway was to feel the responsibility as if everyone were to behave that way.

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This meant that actions that an individual took could be morally right if the individual could justify every person behaving that way in this particular circumstance. What separated this from Kant was that it allowed more room for exceptions. A person could even proceed as a Utilitarian would if they feel this is the right way to behave in that circumstance. The rightness of an action did not rest on a universal principle but the willingness of the individual to take responsibility for an action.

Simon de Beauvoir rejected this idea that rightness could be justified by an individual. Beauvoir instead claimed that if someone were to kill in order to protect others from harm that any claim of the rightness or wrongness of that action could not be completely justified. She called this situation "dirty hands" where an individual commits an act that is wrong, but does so to stop a greater wrong from being committed. The idea that an individual could take complete responsibility and above themselves of all guilt was not one that Beauvoir could endorse.

Both Sartre and Beauvoir did agree that in order to choose moral actions it was inevitable for an individual to take responsibility for their actions. If not then the sense of identity of the individual would begin to crumble and would lead inevitably to despair.


Lutfullo on July 24, 2013:

Commenting on GM 1.13 in BEYOND SELFLESSNESS (Oxford, 2007), Janaway observes: [Nietzsche] sutseggs that language may provide a kind of passive platform for all sorts of reification, and hence for the construction of the fiction that the agent, the doer', is some thing distinct from the sum total of his or her actions or doings. But his explanation here includes a more precisely motivated element, namely the will to power of the weak, whose affects actively exploit the tendency to believe in metaphysical subjects' in order to gain a kind of mastery over the naturally strong by persuading them that to exercise their strength is evil, and to refrain from exercising it good. (p. 112) He then quotes the portion of GM 1.13 that is especially relevant to this last point about a more precisely motivated element and adds: Nietzsche's thought is that prior to the invention of the idea that we are free to be other than we in fact are that our essence resides elsewhere than in the sum of our actual behavior and underlying drives we could not have believed in accountability or blame in the manner required to maintain the moral practice of judging actions good and evil. The notion of a radically free subject of action is required in order to make human beings controllable, answerable, equal, and in particular to redescribe inaction as a virtue of which all are capable and dominant self-assertion as a wrong for which all are culpable. (ibid.)And: It is the reactive affects of the weak, described as 'hiddenly glowing', that drives the need to assign blame and call to account. (ibid)However, in GM 2.10 Nietzsche claims that as a community (in prehistory, temporally or genetically prior to GM 1.13, I assume) grows in power, among other tendencies which develop in penal law is above all the increasingly more resolute will to understand every offence as in some sense *capable of being paid off*, hence, at least to a certain extent, to *isolate* the criminal and his deed from each other Question: doesn't the naturalistic' account in GM 2.10 show that, contrary to Janaway's reading, though the notion of a radically free subject of action may be required to redescribe inaction as a virtue of which all are capable and dominant self-assertion as a wrong for which all are culpable, the notion is NOT required in order to make human beings controllable, answerable, equal"? And, moreover, that it's through the *power* of the community that its citizens develop the practice of "calling to account" and being responsive to such a calling? Is Janaway overstating the role of the metaphysical notion of the radically free subject? And if so, is this symptomatic of a fairly widespread neglect among philosophers of the speculative anthropological claims Nietzsche makes in the GENEALOGY?Just wondering. I should add that I greatly admire Janaway's book.

Rajendiran on July 23, 2013:

I look forward to reanidg the For Beginners book on global warming. Since the author's basic premise is that everyone can do something about global warming, I anticipate that the book will not suggest or recommend that the readers try to find out for themselves the facts about climatology, but instead just accept what they are told about mankind's assault on the atmosphere.

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