Learned, watching a city planner defend a growth boundary line to a room that wanted it moved, that philosophy of nature stops being abstract the moment it has to survive a public hearing. Keeps a marked-up copy of Senate Bill 100 in a drawer, less for the legal language than for the reminder that a good idea about nature still has to become a boring, enforceable line on a map. Takes most hard questions on a walk along the river, since an argument about limits benefits from being made somewhere that has one.