Yet the cost we project for saving civilization would amount to less than $200 billion a year, 1/6 of current global military spending.

Yet I, too, have resisted the idea that food shortages could bring down not only individual governments but also our global civilization.

The cost for saving our civilization would be considerably less than the world's current military spending.

The author has come to agree that food shortages could ultimately lead to the collapse of world civilization.

Now a third and far more significant motivation presents itself: meeting these goals may be necessary to prevent the collapse of our civilization.

They got a better understanding of early human civilization.

Some have 26 vanished from the face of the earth, others are dying slowly, but all have 27 undergone changes as they have come into contact with an 28 expanding machine civilization.