Here’s a link to a typically lucid and insightful piece of Arnold Zwicky’s grammatical analysis. His treatment of word pairs like which/that, for/because, however/but, etc. serves as a foundation for critiques of assumptions of traditional grammar and shows an appropriate respect for the complexity of apparently simple grammatical problems.
http://arnoldzwicky.wordpress.com/2008/12/28/forbecause/
Enjoy!
Herb
Herbert F. W. Stahlke, Ph.D.
Emeritus Professor of English
Ball State University
Muncie, IN 47306
Visit ATEG's web site at http://ateg.org/