Into fragments, disorganized, or confused, as in I tore his argument to pieces. This metaphoric term has been so used since about 1600. Also see go to pieces; pick apart (to pieces); thrill to pieces.
The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.