All complex biological systems have boundaries. Cells have membranes, and some have walls. Multicellular organisms are bounded in skin, and there are many internal barriers that limit access to select agents (e.g. the blood-brain barrier). Swarms, flocks, and herds limit their exposure to predators by aggregating spatially, forming a boundary between in- and out-herd. Human societies live more peacefully with their neighbors when their boundaries are clearly established, often by physical features like mountains and rivers.
This is not a coincidence. For all of these systems, what is most essential to their persistence is their internal organization and selective interfaces with the environment. This organization is not a given, it has been achieved over the chronicle of evolutionary history. For all of these systems, to ‘open them up’ means a breakdown of that organization. Consider what happens to a cell when you ‘open up’ its membrane and allow any agents in the environment to flow freely through it. The organization is lost — the cell is lost.
The United Kingdom has made history by voting for their independence, and taking a step in reaffirming their functional boundaries. We will see more of this in the coming weeks, months, and years. Despite those who cite fragile economic predictions as reasons to ‘remain’ subject to centralized bureaucratic actors, there are much more basic reasons to ‘leave’, and the economists don’t have them in their equations.
In biological systems, boundaries are permeable, but not arbitrarily — they are semi-permeable. Systems which depend on their internal organization for persistence in the face of uncertainty must be free to manage their own semi-permeable boundaries, else they will make a Darwinian exit, making room for those organizations that are more able and willing to do so.