There's still debate over how airplane wings work and how bicycles balance too. It fascinates me that some problems seem to be easier to solve than others. Are

There's still debate over how airplane wings work and how bicycles balance too. It fascinates me that some problems seem to be easier to solve than others. Are they actually easier, or is it that they've had more work put into solving them either because they're more interesting or because a powerful group needed them solved ?