Fundamental Project
ELI5
Your "fundamental project" is the big, deep story you've chosen about who you are and what you're after — it's not something you consciously decided once, but it shapes every smaller choice you make, and truly changing it means reinventing yourself from the ground up, not just tweaking your habits.
Definition
The Fundamental Project, as elaborated by Sartre in Being and Nothingness, designates the original, totalizing self-choice through which the for-itself constitutes itself as a unified, temporal being oriented toward possibilities. It is not an essence given in advance (as in Leibniz's logical determinism) but rather the very structure of freedom as self-projection: the for-itself "makes itself" by choosing, in an originary act that is chronological rather than logical, the global shape of its being-in-the-world. All subsequent, "secondary" choices—particular acts of will, specific desires, surface-level behaviors—relate to the fundamental project not as deductive consequences from a premise, but as partial structures to a Gestalt totality. They are intelligible in light of the fundamental project without being necessary from it, which preserves a genuine domain of "indifferents" where freedom remains unconditioned.
Crucially, the fundamental project is not transparent to reflective consciousness in any straightforward way: it operates as the always-already-chosen horizon within which voluntary deliberation takes place, and the will that appears to contest or revise it in fact draws its meaning from it. This is why the "inferiority complex" analyzed in the second occurrence is not an unconscious mechanism in the Freudian sense, but a freely chosen bad-faith project—a construction whose manifest function (self-deprecation, limitation) conceals its latent function (avoiding the vertigo of radical freedom). Any genuine modification of the fundamental project therefore demands not a piecemeal act of will but a total, radical conversion—a rupture at the level of the original self-choice rather than a local adjustment within its compass.
Place in the corpus
The concept of the Fundamental Project appears exclusively in the Sartrean source (jean-paul-sartre-hazel-barnes-being-and-nothingness-an-essay-on-phenomenological) and functions as the architectonic key to Sartre's ontology of freedom. It sits at the intersection of several cross-referenced concepts: it is the condition of possibility for Freedom (Sartrean) — freedom is not a neutral capacity but always already engaged in a project; it stands in a constitutive tension with Consciousness, since the project is not simply available to reflective self-transparency (the for-itself does not know its project the way Cartesian consciousness knows its contents); and it connects directly to Bad Faith, because bad faith is precisely the misrepresentation of the fundamental project as fixed, external, or unconscious — a denial of one's authorship of the global choice one is. The concept also implicitly articulates the principle "Existence precedes Essence": the fundamental project is what replaces essence for a being who has none prior to its self-constitution.
In relation to the canonical concept of Fantasy as defined in the Lacanian corpus, an instructive structural parallel — and a deep divergence — can be drawn. Both the fundamental project and Lacanian fantasy operate as invisible frames that organize and orient all particular desires and choices, giving desire its "coordinates." But where Lacanian fantasy ($◇a) is a function of the subject's constitutive division by the signifier — a relation to the objet petit a that covers the void of the Real — the Sartrean fundamental project posits a for-itself that is radically transparent and self-constituting, free of any structural lack imposed from outside. For Lacan, the frame (fantasy) must be traversed precisely because the subject did not freely choose it; for Sartre, the fundamental project demands radical conversion precisely because the subject is entirely responsible for having chosen it. The concept of Singularity is also implicitly engaged: the fundamental project is what individuates each for-itself irreducibly, making each human reality a unique Gestalt that cannot be subsumed under universal laws.
Key formulations
Being and Nothingness: An Essay on Phenomenological Ontology (p.476)
the will which presides over this construction finds its meaning in the original project which it can appear to deny, that consequently this construction has a function wholly different from that which it advertises
The phrase "appear to deny" is theoretically loaded: it captures the bad-faith structure whereby the will presents itself as opposing or revising the fundamental project while in fact remaining secretly conditioned by it, so that "the function wholly different from that which it advertises" names the gap between the manifest and latent purpose of any act of self-revision that stops short of radical conversion.