[deepnet]

Rat park was a replication, it was inspired by disregarded evidence of soldiers returning from war.

Most Soldiers who were using 'addictive' drugs simply gave them up when returning home.

A small but constant percentage didn't ~3-5% - Alexander postulated that these types will become addicted to something and it was genotype & circumstance that led to addictive behaviours not the drugs themselves being chemically addictive.

Bruce Alexander has stated that this evidence led him to try to confirm it with his Rat Park experiment.

He plainly showed it was the inhuman conditions that led rats to kill themselves with drugs, well performed, proper controls.

Flew in the face of the prevailing orthodoxy and the political capital of the drug war boogeyman - so no funding for replication. Career suicide to replicate it back then.

It is pretty obviously true, there is hardly a human activity without an associated -oholicism.