This is Stafford Beer's definition of information. It can be found in a number of his books. The one I've got in front of me is on page 283 of "Brain of the Firm", John Wiley & Sons Ltd, 1979 ISBN 0 471 275999.

Stafford Beer is a prolific writer and his books vary in difficulty. One of the more accessible ones is "Platform for Change", John Wiley & Sons Ltd, 1978 ISBN 0 471 061891.

I think John Wiley have recently reprinted many of his books and they are definitely worth a look if you are interested in cybernetics. I've been wrestling with them for over twenty years, often very critically. But what keeps on surprising me is how often something he has said pops into my head, some times years after I read it, and I think how wise.