An interesting question -- or challenge -- was recently put to me some time back by one of the viewers of my Kierkegaard videos. I'd used the phrase "Kierkegaard's existential philosophy," opposing that sort of philosophy to a Socratic or Hegelian idealist, universalizing kind of approach. The issue that got raised -- seemingly focused on the propriety of my speaking in such terms -- bears on the history, rather than the meaning of "existential" and "existentialist"
The worry which my interlocutor expressed was this: One of his well-meaning and fairly well-informed friends had pointed out that Kierkegaard wouldn't have identified his own philosophy as "existentialist," since that term was coined only much later, by Gabriel Marcel. So, it's not a matter of whether Kierkegaard rightly belongs among the "existentialist" philosophers -- in retrospect, of course he does, not least since so many self-identified "existentialist" thinkers explicitly hearken back to his thought, adducing him as a source. The question is more of a lexical one. Did Kierkegaard ever actually call his own approach, his thought, "existential" or "existentialist" philosophy.
If we are to remain at the level of the language itself, charting out the history of the term, then that "-ist" is not a mere suffix, and deciding when it became attached is not simply a quibble. In fact, there's a larger issue at stake -- one which has come up several times in discussion during the Glimpses Into Existence lecture sessions: Is it appropriate to speak of thinkers as "existentialist" who did not actually call themselves -- or their writing -- by that appellation?
This question of appropriateness in its turn also yields to a yet deeper and more central question -- can we specify precisely what "existentialism" consists in, in such a way that it encompasses all of the figures traditionally associated with that name, the spectrum from Kierkegaard to Nietzsche, from Jaspers to Sartre? Is there an internal unity, a coherence to Existentialism that would permit it to be applied retrospectively to thinkers, like Dostoyevsky, Nietzsche, Kafka, or Rilke, who had no inkling that they might be assembled together under that banner?
To swim our way back up out of these murky depths back to the surface, lexicological level, it is worth noting that we ought not to forget that we are confronted with a problem stemming from the fact that Existentialist literature straddles a number of different languages -- Danish, Russian, German, then French and eventually English. While we might well look for some equivalent to the "-ism" -- our English "existentialism" -- we are only likely to find that in French, where Marcel does indeed coin the term "existentialisme," cognate with "existentialiste". These Gallic, extra-e, versions . . . well, they certainly map well onto our English terms.
So, should we say that something that calls itself "existentialism begins in French philosophy, with Marcel's use of the term in the 1930s? That certainly seems off, doesn't it? After all, Heidegger speaks of engaging in analysis of "existentiality of existence" [Existenzialität der Existenz] in Being and Time. A bit later -- and uninfluenced by what is going on in French thought, Jaspers is bringing out works like Vernunft und Existenz and Existenzphilosophie, hearkening back primarily to Nietzsche and Kierkegaard as sources. Shestov, writing in Russian (and quickly enough translated into French) is explicitly speaking of Kierkegaard as bringing forth an "existential philosophy" in his Киргегард и экзистенциальная философия (Kierkegaard and the Existential Philosophy)
So, it's really back to Kierkegaard that we have to look, with his discussions of the "existential" point of view, and his stress upon concrete existence. Do we have any good reasons, based in terminology, to call Kierkegaard one of the "fathers of existentialism"? I think with him we can answer this positively, by looking most specifically at the the Concluding Unscientific Postscript, where he considers the question posed by existential philosophy, i.e. whether an "existential system," analogous to the Hegelian system, could be possible?
It gets a bit trickier, of course, when we are dealing with other early figures in whose works we might find an occasional reference to "existence," but whose reasons to be ranked among "existentialists" depends entirely upon two other criteria -- either because they acknowledgedly influenced later self-conscious "existentialists" who corralled them retrospectively into a movement or at least current of thought, or because their thought clearly grappled with, even embraced and elaborated, some of the themes, issues, and problems the later "existentialist" movement took as their hallmarks.
Who would these early or intermediate figures include? Quite a few writers. Following Kierkegaard, we do have some Danes who are influenced by him -- playwrights like Strindberg and Ibsen -- and the German critic, Georg Brandes, of course. Then, we do have to take Dostoyevsky into consideration -- but we might also think about several other Russian authors from the late 19th and early 20th century, not so much Tolstoy (people always want to bring up "The Death of Ivan Illych") but instead Chekhov.
Who else? The Czech (at that time, "Bohemian") city of Prague supplies us with Kafka and Rilke -- both writing in German, the former exclusively, the latter mainly (supplemented by French) -- neither of whom identify with philosophical perspectives of their times, let alone an "existential" one. There's also Spanish writers to think about -- Unamuno and Ortega y Gasset are both clearly existentialist figures, writing before the term attains its critical mass of usage.
In my own view, the fact that those who self-consciously called themselves "existentialists" saw these earlier writers as precursors is reason enough for us to call them by that name in the present. If we need more, the fact that attentive reading of their texts reveals them dealing with classic themes and adopting approaches associated with later self-declared "existentialists" suffices, I think.