I would begin by asking whether cost benefit analysis has any place in this symposium. It is not directly concerned with finance although one could say that it is a technique for deciding whether a thing is worth the money or, if there is more than one thing, which thing is best value for money. But we need not bring money in at all. The real object is to decide whether a thing, or which thing, is in the best interests of the community.

As such it is a proper prelude to an investment and deserves a place in the symposium.