Editing Contradiction (section)

===Symbolic representation===<!-- This section is linked from [[Barbershop paradox]] -->
In mathematics, the symbol used to represent a contradiction within a proof varies.<ref>{{Cite web|url=http://www.ctan.org/tex-archive/info/symbols/comprehensive/symbols-a4.pdf|title=The Comprehensive LATEX Symbol List|last=Pakin|first=Scott|date=January 19, 2017|website=ctan.mirror.rafal.ca|access-date=2019-12-10}}</ref> Some symbols that may be used to represent a contradiction include ↯, Opq, <math>\Rightarrow \Leftarrow</math>, ⊥, <math>\leftrightarrow \ \!\!\!\!\!\!\!</math>/ , and ※; in any symbolism, a contradiction may be substituted for the truth value "[[False (logic)|false]]", as symbolized, for instance, by "0" (as is common in [[Boolean algebra]]). It is not uncommon to see [[Q.E.D.]], or some of its variants, immediately after a contradiction symbol. In fact, this often occurs in a proof by contradiction to indicate that the original assumption was proved false—and hence that its negation must be true.