Actions are right in proportion as they tend to promote happiness; wrong as they tend to produce the reverse of happiness. By happiness is intended pleasure and the absence of pain.

All desirable things... are desirable either for the pleasure inherent in themselves, or as a means to the promotion of pleasure and the prevention of pain.

All action is for the sake of some end; and rules of action, it seems natural to suppose, must take their whole character and color from the end to which they are subservient.

John Stuart Mill Quotes