I've come to embrace the notion that I haven't done enough in my life. I've come to confirm that one's title, even a title like president of the United States, says very little about how well one's life has been led. No matter how much you've done or how successful you've been, there's always more to do, always more to learn, and always more to achieve.

One of the things I advised Donald Trump to do was to make sure that, before he commits to certain courses of action, he has really dug in and thought through how various issues play themselves out.

And to those nations like ours that enjoy relative plenty, we say we can no longer afford indifference to the suffering outside our borders; nor can we consume the world's resources without regard to effect. For the world has changed, and we must change with it.

A man who took history in his hands, and bent the arc of the moral universe toward justice.

Together, we could open up government and invite citizens in, while connecting all of America to 21st century broadband. We could use technology to help achieve universal health care, to reach for a clean energy future, and to ensure that young Americans can compete - and win - in the global economy.

We have to all shoulder the responsibility for keeping the planet habitable, or we're going to suffer the consequences - together.

I don't regret the fervor, because I do believe, in the African American community but also for other communities, and I know from talking to people, for communities around the world, the election of an African American to the most powerful office on Earth meant things had changed, and not just in superficial ways. That in some irreversible way the world was different.