Cool clock, Ahmed. Want to bring it to the White House? We should inspire more kids like you to like science. It's what makes America great. - Barack Obama

Making your mark on the world is hard. If it were easy, everybody would do it. But it's not. It takes patience, it takes commitment, and it comes with plenty of failure along the way. The real test is not whether you avoid this failure, because you won't. it's whether you let it harden or shame you into inaction, or whether you learn from it; whether you choose to persevere.

For my mother, the world was full of opportunities for moral instruction. But I never knew her to get involved in a political campaign. Like my grandparents, she was suspicious of platforms, doctrines, absolutes, preferring to express her values on a smaller canvas.

The stakes involved in Washington policy debates are often so high — whether we send our young men and women to war; whether we allow stem cell research to go forward — that even small differences in perspective are magnified. The demands of party loyalty, the imperative of campaigns, and the amplification of conflict by the media all contribute to an atmosphere of suspicion. Moreover, most people who serve in Washington have been trained either as lawyers or as political operatives — professions that tend to place a premium on winning arguments rather than solving problems. I can see how, after a certain amount of time in the capital, it becomes tempting to assume that those who disagree with you have fundamentally different values — indeed, that they are motivated by bad faith, and perhaps are bad people.