Go to the link from the Stanford Encyclopedia of Philosophy here: http://plato.stanford.edu/entries/pragmatism/ to help you understand the material on pp. 618-9 in your textbook.
Pragmatism was born from the meeting of a group of thinkers centered around Harvard University called “The Metaphysical Club” (Metaphysics is that branch of philosophy which attempts to understand the nature of being and reality– what is at the essence of things, how do we determine what is real, what existence IS, etc. In other words, mind-blowing stuff.) They were seeking to reconcile scientific theories with man’s need for religious belief.
Thus, they certainly did not believe that ideas were largely worthless.They believed that we could value ideas based upon their practicality, among MANY other things. Be ready to discuss this at the next class meeting.