There are symbiotic parasites and there are more parasites that are only costly to the hosts.
When you swallow food, you drop it directly on tops of hundreds of strains of bacteria which have been harnessed by the body to help digest it.

Every one of those strains represents a tragedy that happened to your ancestors. Each strain came in as a pure parasite. They evolved and your ancestors evolved. The bacilli evolved because they were killing their hosts, and parasites in a dead host die. We evolved because those who could not survive them died.

In the end, the hosts and the parasites which found way to be symbiotic survived.
The Shakers, as you know, were a religious sect which took the St. Paul – Zoroastrian version of Christianity to its logical extreme. They made beautiful furniture and you can take a tour of where the Shakers USED to live.

The Shaker institution killed its hosts.

So did the Shakers’ legitimate ancestors, the Zoroastrians. Z discovered what all institutions that have a huge priesthood to feed discover: You can get a major increase in paying members if you let EVERYBODY in. In the long run, Z killed its racial base and died. But priests and professors don’t CARE about the long run. They become parasites, pure and simple.

Peter and Paul the Tentmaker earned their own livings.