Economics touches everything that has to do with choosing and acting. The choices people make about fundamental aspects of their lives are economic phenomena. No social phenomena can be fully understood without grappling with its economic aspects.
Discussion
Every individual engages in economic calculation when he plans his daily schedule of action—going to work, cooking meals, playing sports, pursuing hobbies, etc. Economics just makes explicit what is involved in everyday decision making.
Consciously or not, all individuals engage in economic thinking and economizing behavior by weighing costs and benefits to allocate scarce resources. Formal economics just articulates the universal logic behind these everyday actions.