Final answer:
The basic economic principle expressed in the lyric is that people can't always get everything they want, but they may be able to get what they need if they try.
Step-by-step explanation:
The basic economic principle expressed in the lyric is that people can't always get everything they want, but they may be able to get what they need if they try. This concept is related to the idea of scarcity in economics, which means that our wants are unlimited but our resources to satisfy those wants are limited. For example, in the scenario of choosing between eating breakfast first or taking a shower first, you have to make a choice because you can't have both at the same time.