When I was 18 I went to college for two years and didn't work for a year which was essential for me, because my identity had been so influenced by my being an actor and I think I just needed to discover what it was to be myself, divorced from all that responsibility.
One of the reasons, surely, why women have been credited with less perfect veracity than men is that the burden of conventional falsehood falls chiefly on them.
In modern pharmacology it's so clear that even if you have a fixed dose of a drug, the individuals respond very differently to one and the same dose.