President Emeritus James B. Conant expects the next 50 years of human history to bring neither total destruction through atomic war, nor total prosperity through science, according to a series of lectures he has recently delivered in Germany.

But Conant does affirm that mankind will survive the perils of the atomic age. Moreover, through the development of solar energy--long a pet theory of his--man's material prosperity will increase despite the exhaustion of some standard fuels like coal.

"The next 50 years will prove that human nature is tough and unyielding to a high degree," he said in part. "Neither the forces of good nor the forces of evil will preyail to the extent that has been prophesied by some writers in the past few years."

New Farming Techniques

An ex-chemist, Conant described how numerous technological discoveries will change many phases of life. New farming techniques will solve the world's food problem, and the use of solar energy may supply an inexhaustible source of power for homes and industries.

Mankind will succeed in avoiding its own destruction "only by the narrowest of margins, and only because, time and time again, when one side or the other was about to take the plunge . . . the expert military advisers could not guarantee ultimate success," he said.

Conant left the University in Jan., 1953.