Professor Alexander explained to me, the idea of addiction we've all got in our heads, that story, comes partly from a series of experiments that were done earlier in the 20th century.
dalinai kyla iš eilės eksperimentų, atliktų XX-tam amžiuje. Jie labai paprasti. Galite juos atlikti šįvakar namie,  jei esate kiek sadistiškas.