This concept was introduced by Arnold van Gennep (1873-1957) and elaborated by Victor Turner (1920-1983) and Edmund Leach (1910-1989).
A 'liminal period' is -- "a betwixt and between" period; where normal life and time stand still or is reversed. Arnold van Gennep analysed the role of life cycle rituals such as birth, puberty, marriage and death, mark stages of transition in an individual's life, where a person makes a transition from one status to another.
According to him, every ritual has 3 stages:
- A stage of separation - the time period when the individual is removed from normal life, often giving up normal daily activities, surrounded by taboos and often enters a ritual status of sacredness. (e.g. during marriage)
- Liminal period - the time period when a person is kept away from society, sometimes physically hidden away, therefore, they are in the society but not a part of it. This is the "betwixt and between" situation when one is suspended as it were in social space and time. (e.g. bride does not leave the house before marriage and does not take part in usual daily activities)
- A final stage of incorporation - after the transition is made, the individual comes out of the liminal period and back to normal life. (e.g. new bride asked to cook a dish at her in-law's house)
Edmund Leach used the concept of liminality to describe what he calls - the marking of structural time/intervals; where important social events mark the oscillations of time, from one period to another. (e.g. Harvest rituals mark the interval between one agricultural cycle and another. The sowing-reaping-sowing cycle is marked at each phase my a ritual.) Leach called this oscillating time as against the concepts of lineal time. There is a sense of reversal, where ordinary life is reversed/stopped. (e.g. during a festival in India called Holi, social norms get reversed. Normal social distances get abandoned; young people take over, hostilities and inequalities are ignored and also in some cases, injustice suffered in regular life acted in reverse, women beat husbands with brooms.)