30 Phil, Chapter 10, Pyrrho of Elis, Touchstone 29: Social Constructs.

A social construct is a shared, non-natural belief created and maintained by groups that shape reality. These are cultural blueprints that encompass shared ideas and frameworks. Many aspects of the world exist independently of humanity and are not social constructs, such as stars, animal reproduction, and gravity. In contrast, things that do not exist in nature and are social constructs include marriage, language, and money.