One of the most important, but that people forget very often. They needed to right to have strange ideas without being chased down and killed due to them.

The Europe science and engineering moved into England much before the economical activity, and as far as I can see, it was mostly because of that one. Some of the greatest minds of the time were literally chased outside of Italy during that move.

Also, it's a right that was missing from most of the world for about a millennium by that time.