Always be nice to people on the way up because you'll meet the same people on the way down. Wilson Mizner
Always be nice to those younger than you, because they are the ones who will be writing about you. Cyril Connolly
Be nice to the whites, they need you to rediscover their humanity. Desmond Tutu
Maybe you don't like your job, maybe you didn't get enough sleep, well nobody likes their job, nobody got enough sleep. Maybe you just had the worst day of your life, but you know, there's no escape, there's no excuse, so just suck up and be nice. Ani DiFranco
Be nice to people goin' up, because you're going to meet them all comin' down. Jimmy Durante
It is nice to be important, but it's more important to be nice. John Templeton