The book is actually a collection of five speeches given in 1975 and 1976; three in the U.S. and two in the U.K.
There are numerous lessons and insights that are highly relevant. Perhaps a selected quote from the author's last speech provides a glimpse at why this work is so worth reading and contemplating. "We have become hopelessly enmeshed in our slavish worship of all that is pleasant, all that is comfortable, all that is material -- we worship things, we worship products. Will we ever succeed in shaking off this burden, in giving free rein to the spirit that was breathed into us at birth, that spirit which distinguishes us from the animal world."