From music to nature to infinity, this episode is all about scales. The team opens with a keyboard ditty as they explore the science behind musical scales - and why major chords sound happy, while minor chords sound sad. They then find themselves tangled up in spider webs, finding out how various structures at different scales club together to give them their extraordinary strength. And finally, the team stares into infinity, visiting Hilbert’s infinite hotel, a mind-boggling thought-experiment which offers a fun and simple answer to an otherwise complex question - how exactly does infinity work? On the pod are Timothy Revell, Anna Demming and Sam Wong. Find out more at newscientist.com/podcasts.