Philosophically, I believe that personal responsibility cannot exist without without the freedom to make bad decisions; and that freedom cannot exist without at least sometimes being exercised.

I think a person should have the right to cycle without a helmet regardless of the fact it may be inadvisable - just like they should have the right to take up skateboarding or skiing or boxing or cheerleading, even if that's even less advisable.

And because I think it's an important right I'm going to exercise it, because a right that exists in theory but not in practice is a right that does not exist.