Jump to content

Bourbaki dangerous bend symbol

From Wikipedia, the free encyclopedia

This is an old revision of this page, as edited by Mmoneypenny (talk | contribs) at 00:31, 23 June 2007 (Undid revision 140018057 by Annoymous666 (talk)). The present address (URL) is a permanent link to this revision, which may differ significantly from the current revision.

The dangerous bend symbol was created by Nicolas Bourbaki and appears in the margins of mathematics books written by the group. It is analogous with a street sign that indicates a "dangerous bend" in the road ahead. Bourbaki, and those who later adopted the symbol, would use it to mark passages that were tricky on a first reading or contained an especially difficult argument. For example, computer scientist Donald Knuth uses it in his textbooks.

References

File:Rkinch db.gif
Knuth's "Dangerous Bend" sign.

See also