Leitmotif

Leitmotif

/ˈlītmōˌtēf/

noun

a repeated theme that shows up often, usually in art, literature, or music

Every age has its leitmotif, a set of beliefs that explains the universe, that inspires or consoles the individual by providing an explanation for the multiplicity of events impinging on him. 

– Henry Kissinger (1923 – 2023)