Freud argues that civilization is intrinsically inimical to human happiness. The process of "civilizing" the human being involves stifling many of the sexual impulses that lead most directly to pleasure. Freud also notes that participation in civilized life entails the renunciation of one's aggressive impulses. Thus, to be civilized we must do without the two strongest claims to our instincts, sex and violence. Stifling two of our most basic drives does lead to discontent but I guess we can't have everything! Most of this excerpt is taken directly from the GradeSaver site. Please check it out in the source link below.