I think this very much depends on the circumstances. Few working-age men walk in my neighborhood, and some people seem a little uneasy seeing me walking. They don't know what to make of me.

On the other hand, if I walk a dog it is clear what I'm doing, and people are quick to share a smile. It seems like many people are uncomfortable unless your activity fits into a pattern they're familiar and comfortable with.

I remember a teacher who cycled to work every day, along a coastal route. Because he saw the same people so often, he set himself a goal to smile at all he recognised so they'd smile back.

Last time we spoke, he was still battling one obstinate hold-out (while reminds me of an old joke - 'smiles' is actually the longest word in the english langugage because there's a mile between the s's).

If "smiles" is the longest, how do you explain "similes"?

They must not have heard of beleaguered either.

Touche.

But more seriously, an imile is orthognal to the traditional one and as a result there is zero space between the s's.

There's a great circle joke in here somewhere. I'm just not sure how to rotate the conversation into it.

I think that largely depends on where you are, and what the cultural norms are. I go out of my way to smile at everyone I see, and most people smile back, even if it takes them a double-take before they do. I'll never not smile at someone, because it's a known stress reliever to do so, especially when my smile elicits another's smile.