Editing Vagueness (section)

== Importance ==
The concept of vagueness has philosophical importance. Suppose one wants to come up with a definition of "right" in the moral sense. One wants a definition to cover actions that are clearly right and exclude actions that are clearly wrong, but what does one do with the borderline cases? Surely, there are such cases. Some philosophers say that one should try to come up with a definition that is itself unclear on just those cases. Others say that one has an interest in making his or her definitions more precise than ordinary language, or his or her ordinary concepts, themselves allow; they recommend one advances [[precising definition]]s.<ref name="Williamson.1994">[[Timothy Williamson|Williamson, T]]. 1994. ''Vagueness'', {{page needed|date=April 2017}}. London: Routledge. <br />The history of the problem of vagueness is traced, from the first [[Sorites Paradox]] to contemporary attempts to deal with higher-order vagueness such as [[many-valued logic]], [[supervaluationism]], and [[fuzzy logic]]. Technicalities are kept to a minimum to favour a clear account, extremely useful to both students and researchers.{{citation needed|date=April 2017|reason=Specific claims regarding the usefulness of a source to readers of this article.}}</ref>

=== In law ===
Vagueness is also a problem which arises in law, and in some cases, judges have to arbitrate regarding whether a borderline case does, or does not, satisfy a given vague concept.  Examples include disability (how much loss of vision is required before one is legally blind?), human life (at what point from conception to birth is one a legal human being, protected for instance by laws against murder?), adulthood (most familiarly reflected in legal ages for driving, drinking, voting, consensual sex, etc.), race (how to classify someone of mixed racial heritage), etc.  Even such apparently unambiguous concepts such as biological sex can be subject to vagueness problems, not just from [[transsexual]]s' gender transitions but also from certain genetic conditions which can give an individual mixed male and female biological traits (see [[intersex]]).

{{anchor|Legal principle}}<!--- courtesy under WP:LINK, [[Albert Haddock]] links here]] -->
In the [[common law]] system, vagueness is a possible [[legal defence]] against by-laws and other regulations.  The legal principle is that delegated power cannot be used more broadly than the delegator intended. Therefore, a regulation may not be so vague as to regulate areas beyond what the law allows. Any such regulation would be "void for vagueness" and unenforceable.  This principle is sometimes used to strike down municipal by-laws that forbid "explicit" or "objectionable" contents from being sold in a certain city; courts often find such expressions to be too vague, giving municipal inspectors discretion beyond what the law allows. In the US this is known as the [[vagueness doctrine]] and in Europe as the [[principle of legal certainty]].

=== In science ===
Many scientific concepts are of necessity vague, for instance [[species]] in biology cannot be precisely defined, owing to unclear cases such as [[ring species]].  Nonetheless, the concept of species can be clearly applied in the vast majority of cases.  As this example illustrates, to say that a definition is "vague" is not necessarily a criticism. Consider those animals in Alaska that are the result of breeding [[Husky|huskies]] and [[wolf|wolves]]: are they [[dog]]s? It is not clear: they are borderline cases of dogs. This means one's ordinary concept of doghood is not clear enough to let us rule conclusively in this case.