Prevent

Prevent is from pre-vent. Pre-vent is to let people with different opinions vent their grudge early to reduce the tension. This is probably the meaning of prevent when it was coined. Now prevent generally means suppress something from happening. It represents the transformation of dominant ideas over time.

There is a parallel in ecological system. In a newly opened field, many small species flourish, or pre-vent. But as dominant large species, such as large trees, take over, the shade of large trees prevent small species from growing.

 Biological diversity declines in a mature landscape, just like diversity in ideas declines in a mature society.