CHICAGO (AP) — Former President Barack Obama urged community organizers and social innovators to be patient in their pursuits of wide-scale community change.

Obama made the plea during a talk Monday at the Obama Foundation summit in Chicago.

The former president noted that patience is needed because societies are “complex, organic things that you don’t turn (like) switches. They evolve. They shift. They change.”

Obama talked extensively about his background as a community organizer, his experiences as a politician and writing his book.

He joked writing the book is a “brutal” process he says is causing strain in his marriage now that Michelle Obama has launched her book tour.

Obama delivered his remarks from a plush chair, engaging in a conversation with author Dave Eggers.

The Obama summit is a two-day conference that brings together civic innovators and community activists from around the world to network, exchange ideas.

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