Bourbaki dangerous bend symbol: Difference between revisions
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[[File:Dangerous bend symbol.png|thumb|left|Knuth's "Dangerous Bend" sign]] |
[[File:Dangerous bend symbol.png|thumb|left|Knuth's "Dangerous Bend" sign]] |
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The '''dangerous bend''' symbol ☡ ([[unicode]] number x02621) was created by the [[Nicolas Bourbaki]] group of mathematicians and appears in the margins of [[mathematics]] books written by the group. It resembles a [[road sign]] that indicates a "dangerous bend" in the road ahead, and is used to mark passages tricky on a first reading or with an especially difficult argument.<ref>Steven G. Krantz (2011), ''[http://books.google.com/books?id=mMZBtxVZiQoC&pg=PA92 The Proof Is in the Pudding: |
The '''dangerous bend''' symbol ☡ ([[unicode]] number x02621) was created by the [[Nicolas Bourbaki]] group of mathematicians and appears in the margins of [[mathematics]] books written by the group. It resembles a [[road sign]] that indicates a "dangerous bend" in the road ahead, and is used to mark passages tricky on a first reading or with an especially difficult argument.<ref>Steven G. Krantz (2011), ''[http://books.google.com/books?id=mMZBtxVZiQoC&pg=PA92 The Proof Is in the Pudding: The Changing Nature of Mathematical Proof]'', Springer, ISBN 0387489088, p. 92.</ref> Others used variations of the symbol in their textbooks, and computer scientist [[Donald Knuth]] used a more realistic [[Traffic sign|roadsign]] depiction.<ref>Donald Ervin Knuth (1984), ''[http://books.google.com/books?id=hEYuAQAAIAAJ The TeXbook]'', Addison-Wesley, ISBN 0201134489.</ref> |
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The Changing Nature of Mathematical Proof]'', Springer, ISBN 0387489088, p. 92.</ref> Others, including computer scientist [[Donald Knuth]], used variations of the symbol in their textbooks. |
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==Typography== |
==Typography== |
Revision as of 06:32, 4 September 2011
Certains passages sont destinés à prémunir le lecteur contre des erreurs graves, où il risquerait de tomber; ces passages sont signalés en marge par le signe ☡ («tournant dangereux»)
Some passages are designed to guard the reader against serious errors, where he risks falling; these passages are signposted in the margin by the sign ☡ ("dangerous bend")
Nicholas Bourbaki's description of the symbol in several textbooks[1]
The dangerous bend symbol ☡ (unicode number x02621) was created by the Nicolas Bourbaki group of mathematicians and appears in the margins of mathematics books written by the group. It resembles a road sign that indicates a "dangerous bend" in the road ahead, and is used to mark passages tricky on a first reading or with an especially difficult argument.[2] Others used variations of the symbol in their textbooks, and computer scientist Donald Knuth used a more realistic roadsign depiction.[3]
Typography
In the LaTeX typesetting system (version 3), the dangerous bend symbol can be written as:[4]
\begin{danger} ... \end{danger} \begin{ddanger} ... \end{ddanger}.
References
- ^ See, for example, Théorie des ensembles, p. I-8.
- ^ Steven G. Krantz (2011), The Proof Is in the Pudding: The Changing Nature of Mathematical Proof, Springer, ISBN 0387489088, p. 92.
- ^ Donald Ervin Knuth (1984), The TeXbook, Addison-Wesley, ISBN 0201134489.
- ^ Frank Mittelbach, Michel Goossens, Johannes Braams, David Carlisle, Chris Rowley, Christine Detig, and Joachim Schrod (2004), The LaTeX Companion, Chapter 3: Basic Formatting Tools, Addison-Wesley.