“The highest goal of life is to create happiness for oneself and others. Of these two things, bringing happiness to others is a nobler goal.”

Source: You Learn by Living (1960), p. 95

1990s, Copyleft: Pragmatic Idealism (1998)
Context: Every decision a person makes stems from the person's values and goals. People can have many different goals and values; fame, profit, love, survival, fun, and freedom, are just some of the goals that a good person might have. When the goal is to help others as well as oneself, we call that idealism.
My work on free software is motivated by an idealistic goal: spreading freedom and cooperation. I want to encourage free software to spread, replacing proprietary software that forbids cooperation, and thus make our society better.

As quoted by Ernst Straus in Einstein: A Centenary Volume by A.P. French (1980), p. 32.
Attributed in posthumous publications
Variant: "if you want to be a happy man, you should tie your life to a goal, not to other people and not to things." A quote from Ernst Straus' memoir of Einstein in Albert Einstein: Historical and Cultural Perspectives edited by Gerald Holton and Yehuda Elkana (1982), p. 420 http://books.google.com/books?id=CNuwE3NL1QgC&lpg=PP1&pg=PA420#v=onepage&q&f=false

The Power of Positive Living (1992), p. 63

Rules of the Game: The Style Diaries (2007)
Context: A lot of people make the mistake of trying to defend principles in relationships. My goal is long-term happiness. And I make choices that aren’t going to undermine that goal.