Infinite Regress infinite regress is the situation in which an explanation or a justification requires another of the same kind, and that one requires another, and so on without end. If A is explained by B, and B must be explained by C, and C by D, and there is no stopping point, we are in a regress. The regress is often taken to be vicious—to show that the original explanation or justification fails—because it never reaches a ground. Why think that? The thought is that explanation or justification must somewhere come to rest; if it does not, then nothing has been explained or justified. The infinite regress thus functions as a limit-concept: it marks the point at which a certain form of reasoning breaks down because it can find no purchase. Classical instances include the regress of causes (if every event has a cause, and causes are events, then we have a chain of causes stretching backward without limit—so either the chain has a first member, which is uncaused, or the whole chain is unexplained), and the regress of justification (if every belief must be justified by another belief, and that by another, then either we reach a belief that is self-justifying or foundational, or we have an infinite chain of reasons—and an infinite chain, it is said, justifies nothing). In both cases, the structure of the regress is used to motivate the need for something that stops the regress: an uncaused cause, a foundational belief. The limit that the regress exposes is the limit of the kind of explanation or justification that requires a prior item of the same kind. Not every regress is vicious. In mathematics, an infinite sequence or series can be well-defined and even convergent; the sequence of natural numbers has no last member, but that does not make it incoherent. The question is whether the regress in a given case is benign or vicious—whether the infinite continuation is acceptable or whether it undermines the aim of the inquiry. For a regress to be vicious, it is usually held that the regress must be of a kind that was supposed to terminate: we were seeking a cause, a reason, a definition that would serve as a ground, and the regress shows that no such ground is to be had within the framework we adopted. The regress is then a reductio of that framework or of the assumption that generated it. The strategy of generating a regress to refute a position has been used across philosophy. If you say that every event has a cause, the regress of causes can be used to push you toward a first cause—or to reject the demand for a complete causal explanation. If you say that meaning is always a matter of interpretation, and that every interpretation is itself in need of interpretation, the regress can be used to suggest that meaning must somewhere be "given" rather than interpreted—or that the demand for a final interpretation is misplaced. The regress is a tool: it reveals a structure and forces a choice among accepting the regress, introducing a stopping point, or abandoning the form of inquiry that produced the regress. In the context of limits, the infinite regress is a limit of a certain kind of reasoning. It shows that we cannot complete a certain task—cannot trace all causes back, cannot justify every belief by another belief—within the terms we have set. Whether that limit is a defect or a feature, and how we should respond to it, are questions that have shaped metaphysics and epistemology. The regress stands as a reminder that not every "why?" can be answered, and that the demand for completeness may itself need to be limited. [role=marginalia, type=objection, author="Reviewer", status="adjunct", year="2026", length="42", targets="entry:infinite-regress", scope="local"] Whether a regress is "vicious" often depends on one’s prior commitment to foundationalism; coherentist and infinitist views reject the demand for a last reason. See Also See "Limits" See "Infinity"