Something he does has an intrinsic value, e.g., cleaning his room has an intrinsic value, i.e., a clean room. It may also have an derived value, e.g., a praise from mom.
Teach him to focus on the intrinsic value and the happiness he can derive from it, e.g., looking at the clean room and being happy about the accomplishment.
A master of his own life cares about the intrinsic value, one with a slave-mentality only cares about the derived value.
