Just think, one smile, or small act of kindness, even just politeness could brighten someone else's day and inspire them. It's a chain of smiles! Exactly the same as one frown, or one act of negativity or just being rude, could ruin someone's mood. And who are you to bring other people down for no reason? Keep positive, think positive and act positive! And your positivity might just spread :) even if you feel like you've had a bit of an average or crappy day. Just give someone a smile. You never know what you could do :)