Limit limit is perhaps the most general and the most elusive of the concepts treated in this volume. We speak of the limits of knowledge, the limits of language, the limits of tolerance, the limits of a function, the limits of the city. In each case we mean something different—a boundary, a maximum, a threshold, a constraint—and yet we sense that something common is at work. To be limited is to be bounded, to be constrained, to be finite. The limit is what defines the scope of something by marking where it ends or what it may not exceed. This volume is devoted to limits; it is therefore fitting to ask what a limit is—and to recognise that in asking we may be approaching a limit of our own. In ordinary usage, a limit is often spatial or quantitative. The limit of the land is the boundary beyond which it does not extend. The speed limit is the maximum velocity permitted. The limit of a sequence in mathematics is the value that the sequence approaches. In each case we have something that is bounded—by a line, a number, or a value—and the limit is the boundary itself or the value that marks it. The concept is so familiar that we rarely pause over it. Yet as soon as we try to generalise—to ask what all limits have in common—we run into difficulty. Is the limit part of what it limits or external to it? Does the limit belong to the thing limited or to the space or domain beyond? If I stand at the edge of a cliff, is the limit at my feet or at the point where the rock gives way to air? The limit seems to be neither fully here nor fully there; it is the boundary, and the boundary is the neither-nor that divides. In philosophy, the theme of limits has been developed in connection with human knowledge and with the structure of reality. We are limited knowers: we cannot survey all of nature, we cannot secure our beliefs against every doubt, we cannot step outside our perspective to compare it with reality as it is in itself. The recognition of these limits has been used to motivate humility, to refute pretensions to absolute knowledge, and to mark the boundary between what can be known and what must be believed or left open. The limit of knowledge is not a line we can point to on a map; it is a structural feature of our condition—the fact that our cognition is finite, embodied, and historically situated. To acknowledge the limit is not to know where it lies in every case but to know that it exists. In ethics and politics, limits take the form of constraints on action—rights that may not be violated, boundaries that may not be crossed. The limit here is normative: it is what ought not to be exceeded. The question of whether such limits are discovered or posited, and of how they can be justified, has been central to moral and legal philosophy. The limit is also internal to the self: we speak of the limits of endurance, of patience, of what we can forgive. These are limits of capacity—points at which we break or cease to function in a certain way. They are both factual (we do have such limits) and normative (we may be obliged to respect the limits of others, or to push against our own). In mathematics, the concept of limit has been given a precise formulation that has proved fundamental to analysis and to the understanding of continuity and infinity. A sequence approaches a limit if, beyond a certain point, its terms remain arbitrarily close to a fixed value. The limit need not be attained—the sequence may never equal the limit—but the structure of approach is well-defined. This technical notion has philosophical resonance: it shows that we can reason rigorously about the infinite and the continuous by means of the limit, and that "reaching the limit" can be understood in a way that does not require a final step. The limit is the point of convergence, the value that would be reached if the process were completed—and the "if" marks the idealisation that makes the mathematics possible. The limit has also been thematised as that which we cannot think or say without contradiction. There are propositions that seem to point toward their own limit: "This statement is false," "Nothing can be said about the ultimate." The limit here is the boundary of sense—the point at which our concepts or our language break down. To try to think the limit of thought is to risk paradox; to try to say what cannot be said is to risk nonsense. And yet we seem to be able to refer to the limit, to gesture toward it, to organise our thinking around the knowledge that there is something we cannot do. The limit is thus both inaccessible and inescapable—we cannot cross it, and we cannot avoid recognising it. In the life of the individual and the community, limits are experienced as finitude, as mortality, and as the constraints of circumstance. We are limited by the time we have, by the bodies we inhabit, by the histories and institutions that shape us. To affirm these limits is not necessarily to resign ourselves to them; it can be to understand the conditions within which freedom and meaning are possible. The limit is then not only a barrier but a condition—that which makes form possible by bounding the formless. A river is bounded by its banks; without the banks it would be a flood. The limit can be productive as well as restrictive. This volume has examined many particular limits—the horizon, the edge, the end, the threshold, the unsayable. Each entry has approached the theme from a different angle. What they share is the recognition that to be finite is to be limited, and that the examination of limits is not a marginal task but a central one for philosophy. To understand what we can know, what we can say, and what we can do requires understanding what we cannot. The concept of limit is the concept under which that understanding is organised. We do not here propose a single definition of limit—the concept may be too fundamental for that, or it may be a family of related notions. We propose only that to reflect on limit is to reflect on the boundaries that define us, and that such reflection is itself an activity that takes place within limits—including the limit of this entry, which must now end. [role=marginalia, type=objection, author="Reviewer", status="adjunct", year="2026", length="42", targets="entry:limit", scope="local"] A single umbrella concept of "limit" may obscure important differences between logical, physical, normative, and phenomenological boundaries. See Also See "Limits" See "Infinity"