"We want it both ways: We want love to feel like madness, and we want it to last an entire lifetime. That sounds terrible." Watch Mandy Len Catron's full TED Talk here: http://t.ted.com/9EEoa1Z | TED

Are you a giver, a taker or a matcher? Here's the difference — and why it matters. Watch Adam Grant's full talk here: http://t.ted.com/fHKBnar | TED

As a teenager Ethan Lindenberger went on Reddit and asked: "Where do I go to get vaccinated?" despite having parents that were against it. Watch his full talk to learn what happened next: http://t.ted.com/JbUYHZo | TED