“Drugs cause addiction.” This was the conclusion drawn from repeated rat experiments in numerous university research centres in the 1950s and 60s. These studies had involved the use of tiny cages with contraptions that allowed isolated animals to drink drug-laced sugar water or inject drugs by pressing a lever. The rats consumed large amounts of heroin, morphine, amphetamine, cocaine and other drugs, sometimes not eating and dying through neglect. This led scientists to conclude that the drugs had innate powers that made them irresistible to rats and humans alike.