BOSTON—Robert Reich, former President Bill Clinton’s first secretary of labor, announced Wednesday that he will be seeking the Democratic nomination for Massachusetts governor on a platform of improving the economy.

In an interview after the announcement, Reich said that a November visit to a Harvard class was a “catalyst” for his decision to run.

Reich said that the discussion he had with the class, Religion 1529: “Personal Choice and Global Transformation,” about personal courage was a “profound moment” for him, and that later that day he began to explore a run for governor.

“I left that class thinking to myself—this state is a mess and I need to run for governor,” Reich said. “It was from that moment that I began to think I’ve talked the talk a lot, now it’s time to walk the walk.”

Brian Palmer, who created and teaches Religion 1529, said he and the head teaching fellow, Kate Holbrook, thought the experience of interviewing people “whose courage and commitment have made a difference in the world” would be “transformative” for students and teachers.

But he said he never expected the guests to come away changed men and women.

“She and I knew that we were dealing with, powerful themes and material and examples of lives,” Palmer said. “But we assumed that our guests were already sort of fully formed, that they were not learning and growing from the encounter as much as we were.”

The transformative moment, as Palmer and the candidate recall it, came when Reich remembered for the class a childhood moment of courage, standing up to a neighbor who had said that he would have Reich’s dog put to sleep.

“[Reich] said that at the end of that verbal confrontation, he felt as if he understood that he did not need to be afraid of anyone in the whole world,” Palmer said.

Reich, a 55-year-old man who stands 4’10 1/2” tall, was frequently self-deprecating in his speech announcing his run for the governor’s seat.

Reich started out with a joke, as he pulled out a wooden step to stand on.

“At least I stand firm on my platform,” Reich quipped.

But Reich quickly got down to business.

“I became secretary of labor to fight for the working women and working men of America,” Reich said. “I was a member of an administration that oversaw the longest economic expansion and new growth in history. We added millions of new jobs.”

Reich contended that there is a “vacuum of leadership” at the state level, particularly when it comes to the economy, and said that in his campaign he would be “focusing like a laser beam on the economy and on jobs.”