I believe, that if you are not in a rush, and you are not otherwise preoccupied, you should look to say hello to just about everyone you encounter, within reason, on your journey. That is my personal policy, and that appears to be the policy of a lot of other people as well, if not enough people, circumstances permitting.
It is a gesture, an act of consideration, for a stranger. It is the sort of thing that can make a great difference to an individual. You are sending the message, that you are open to communicating with them, they matter.
Aside from the fact that that may mean a great deal to someone, it is a sign of unity with that person. And it is a demonstration of goodwill to everyone.
I think it really is possible to make a big difference to the world with small actions of kindness to strangers, because it can be contagious. It will be remembered, and it's likely it will be repeated. That's how it goes. It should always go that way.
They say Divide and Conquer, I say Unite and Conquer, and we are not on this earth to be strangers to each other.
Obviously, if someone is running fast towards you with an object in their had, that might qualify as an exception. Or maybe not. You know yourself. I probably would say hello.
