His 'philosophy of life' [=his way of living] is to treat people as he would like to be treated.
My 'philosophy' is to live and let live. [=let other people live the way they want to]
Her main cooking 'philosophy' is to use only fresh ingredients.
(..) - Listen to me, son. - Yeah, go ahead. You're a lot like your father. You really are, Peter, and that's a good thing... ...but your father lived by a philosophy, a principle, really. He believed that if you could do good things for other people... ...you had a moral obligation to do those things. (..)2012 The Amazing Spider-Man