A student puts up her hand in a primary school science class.
“How do plants breathe?”
The teacher could answer this question in several ways. One of them could be to give the “textbook” answer – every leaf has pores out of which plants inhale carbon dioxide and exhale oxygen. Plants breathe through their leaves.
Alternatively, he could use this question as a prompt. He could tell children about how plants deliver water to their highest branches. A giant redwood tree that is 100 meters tall transports water from its roots to a leaf on its highest branch by simply breathing. In this manner, trees are able to move water to the height of a thirty storey building without a pump.
Every question is a prompt. At times, direct answers are valuable. But otherwise, questions can tell us something about our listener’s inclinations to embark on an interesting journey. Or to spark wonder in the eyes of little children in a science class.