Conversation

Daughter has reached the age of asking "why?" to everything.

"hold on to that cup with both hands"
"why?"
"i don't want you to drop it"
"why?"
"It's made of glass, and if you drop a glass thing it can break"
"why?"
"because glass is brittle"
"why?"
"because supercooling molten silicon dioxide makes an amorphous solid which is weaker than the crystalline form"
"why?"
"the crystalline form has a tetrahedral lattice of ionic bonds"
"why?"
"because one silicon atom can bind with four oxygen"
"why?"