To me, interaction design is multi-disciplinary to it’s core. It reflects the need of working with diversity as a main approach, both within teams and for our people. I always adopt methods from behaviour psychology and user - centered design. I am also a believer of systematic thinking and service design frameworks.
My favourite quote is “We should design for a society reflecting it as it is” - meaning we should always design for a society represented as it looks like, for the real people out there.