You can’t have your cake and eat it, too

The popular expression "you can't have your cake and eat it, too" and "there is no such thing as a free lunch" relate to the basic economic problems of scarcity, choice, and opportunity costs.

Scarcity is too few goods and services to satisfy all wants and needs.
Choices are made based off a person's values.
Value judgments must be made, and the person must know the tradeoffs and opportunity costs before making a decision.

A value judgment is the relative importance a person assigns to an action or alternative.
A tradeoff is the giving up one thing for something else.
Opportunity Cost is the cost of a purchase or decision measured in terms of a foregone alternative; what was given up to make a purchase or carry out a decision

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