A Psychology for Living: personal construct theory for professionals and clients by Peggy Dalton and Gavin Dunnett. Published by  John Wiley and Sons, Chichester, 1992;  227 pages; £12.95.

The gods did not reveal, from the beginning,

All things to us; but in the course of time,

Through seeking we may learn, and know things better.

But as for certain truth, no man has known it,

Nor will he know it; neither of the gods,

Nor yet of the things of which I speak.

And even if by chance he were to utter

The final truth, he would himself not know it;

For all is but a woven web of guesses.