I believe that the free enterprise system is the greatest engine of prosperity the world's ever known.

There is no excuse for not trying.

And I will do everything that I can as long as I am President of the United States to remind the American people that we are one nation under God, and we may call that God different names but we remain one nation.

Every four minutes, another American home or business goes solar.

What I consistently say to young people - I say it in the United States, but I'll say it here in Germany and across Europe: Do not take for granted our systems of government and our way of life. I think there is a tendency, because we have lived in an era that has been largely stable and peaceful, at least in advanced countries, where living standards have generally gone up, there is a tendency I think to assume that that's always the case.

Sometimes they're nothing, sometimes they're something, sometimes there's a connection that years later may show up. All of this information is useful.

As tough as things have been, I am convinced you are tougher. I've seen your passion and I've seen your service. I've seen you engage and I've seen you turn out in record numbers. I've heard your voices amplified by creativity and a digital fluency that those of us in older generations can barely comprehend. I've seen a generation eager, impatient even, to step into the rushing waters of history and change its course.