Fischer told reporters he did not bear a grudge against his former boss, ex-chancellor Gerhard Schroeder, who sealed the fate of their so-called Red-Green government by calling early elections last year which they lost.
"I don’t look back in anger," he said. "Even if we had won I would have left after a year."
Fischer said that although he loved politics, he had reached an age at which he no longer needed the rush.
"There is a big difference between passion and addiction," he said.
Observers noted the irony that Fischer, who was a photographer, a Maoist radical and a taxi driver in his youth but never earned a degree was now taking a job at one of the world’s premier universities.
The sharp-tongued orator has signed a one-year contract to teach international crisis management from September and joined the New York-based Council on Foreign Relations think tank.
