A lot of people, and this includes everybody from philosophers and economists to ordinary people believe that human nature is fundamentally selfish, that we're only ever really motivated by our own welfare.
Mucha gente, esto atañe a todos desde filósofos y economistas  hasta la gente común, cree que la naturaleza humana  es fundamentalmente egoísta, que solo estamos realmente motivados  por nuestro propio bienestar.