Giles has taught himself to play the guitar, bass, and piano since he graduated from college. This weekend Clara decided she'd learn the guitar too. It's such a convenient instrument; it makes people sing together.
Giles showed her D, G, A, and B minor. "These are all you need to play any pop song or worship chorus."
Felix (obsessed with organic chemistry this summer): "Oh! They're nitrogen, hydrogen, oxygen, and carbon."
That's right. Now the kids can build anything. Any song, or any compound.