Al Gore scared many with his Inconvenient Truth documentary, identifying the dire consequences of global warming, thus mobilizing lots of action groups and businesses to take the issue more seriously. Now, his latest TED talk has a much more upbeat note. Yes, there are many challenges, still, but we’ve already started changing, he says. “When any great moral challenge is ultimately resolved into a binary choice between what is right and what is wrong, the outcome is foreordained because of who we are as human beings. That is why we’re going to win this.”