Where the words come from
Households and firms meeting in the market for goods and services and the labour market, consumers trying to maximise total utility, or satisfaction, given their budget constraint (chapter 6 introduction and 6.1), every business trying to earn a profit with profit as revenue minus cost, and self-interest as a simplification alongside giving to charity, family and friends — Principles of Economics 2e, OpenStax, licensed CC BY 4.0. https://openstax.org/books/principles-economics-2e/pages/1-3-how-economists-use-theories-and-models-to-understand-economic-issues and https://openstax.org/books/principles-economics-2e/pages/6-1-consumption-choices and https://openstax.org/books/principles-economics-2e/pages/7-1-explicit-and-implicit-costs-and-accounting-and-economic-profit and https://openstax.org/books/principles-economics-2e/pages/2-3-confronting-objections-to-the-economic-approach and https://openstax.org/books/principles-economics-2e/pages/6-introduction-to-consumer-choices. Changes: 1.3's circular flow of households and firms condensed into one sentence, with the government added; 6.1's utility and 7.1's profit put into the card definitions; 2.3's "the assumption that individuals are purely self-interested is a simplification" and its charity, family and friends condensed. Ours: government as a third agent and social welfare as its objective, scarcity for each agent, the weighing of benefits against costs, giving counted as part of utility, managers aiming for growth or sales, value judgements and elections, the card examples, the checks and the mistake note's figures; British spelling.
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