In the bike car on the train, some of the seats are arranged in sets of 4 seats facing each other. Now, this would be really great, except that the seats are very very close together such that you end up knocking knees. Of course, somehow people are able to arrange their legs so that you aren’t poking against each other. It’s actually pretty amazing how strong the social taboo of touching strangers is, and how widely accepted this is. We may have different ideas of how far our personal space extends, but it seems like people all agree that actually touching someone else (except in extenuating circumstances like an extremely crowded place) is not okay.