If you compare yourself with others, you may become vain and bitter

If you compare yourself with others, you may become vain and bitter; for always there will be greater or lesser persons than yourself. 

If you think you are too small to make a difference, try sleeping with a mosquito. Now you get the point, don't laugh. Have a heart that never hardens, a temper that never tires, a touch that never hurts. You can tell more about a person by what he says about others than you can by what others say about him. Whatever you can do, or dream you can, begin it.