Wow! I haven't heard that before, but I love it. Very visual! A peg is a piece of wood or metal that you use to hold other objects. This phrase is saying that each word can hold an entire idea, the same way that a peg could hold a coat or bag. Image of pegs in a pegboard, if this helps : http://www.multicraftplastics.com/accessories_supplies/images/PegBoardHooks.jpg

Definition of a peg to hang (something) on British : something (such as a fact or issue) that is used as support or a reason for something said or done <He used the incident as a peg to hang his theory on.> Check it! http://www.merriam-webster.com/dictionary/a%20peg%20to%20hang%20(something)%20on

everything you say , in the future will be a step forward to create your idea

"All words are pegs to hang ideas on." > Whatever said are said in such a way as to to highlight ideas on...