People in the past, slept 2 or 3 times per day. First is daily sleep or nap in afternoon. Second time is after sunset, between 8 and 12. After midnight people were awake for couple hours. Usually ,majority of them read book or talk with each other and even had guests at night. Last phase of sleep is, begins from 2 and continues for 7 hours. It is a result of unemployment and poverty. Due to, people could not do anything without light after sunset. Only wealthy people could amount of candles and do whatever they want. As a rule, we know that in the past 85 per cent of people were poor, so they could not allow theirselves that kind of purchase. Therefore people slept. The second reason in my point of view ,that people now are more busy than in the past. In the century of innovations ,people to be successful need to study and work day and night. Students sleep for 3-4 hours because they burn the midnight oil. Adults sleep less, seeking a job. Moreover, due to overpopulation level of l...