Brains are delicate things…
Wealth is kind of like an increase in development- the resources and good stuff we (could) have- clean air, good food, safe work places etc.
Illth is perverted “growth”, where a big road smash adds to the economy’s size (and ‘health’) because of the work provided for tow-trucks, blood banks, hospitals, funeral parlours. Illth is nuclear power plants, whose decommissioning costs make the economy look good!
Illth was a term coined by John Ruskin. See also Buckminster Fuller, EF Schumacher and stuff on the diseconomies of growth & “externalities” http://www.nous.org.uk