Mass hysteria is a phenomenon where collective illusions, real or imaginary, are spread across a population or society through rumours or fear. Mass hysteria is usually characterised by a loss of rational thinking and extraordinary emotional responses.

A significant example of mass hysteria in India was the case of some Ganesha idols drinking milk. On 21 September 1995 a small temple in Delhi reported that their idol of Lord Ganesha was drinking the milk offered to it. Across the country a mass frenzy took place with people rushing to temples to feed Lord Ganesha milk. Some people said they believed Vishnu’s final avatar had arrived, signalling the end of the Kalyug. Stores ran out of milk, Hindus celebrated the day as if it were Holi or Diwali. It was one of the biggest stories to come out of South Asia that year, with media outlets across the globe carrying the story. However, abroad, it reinforced the stereotype that India was a “nation of Godmen, snake-charmers and miracles,” the journalist Dilip Cherian noted.

In Satara, the rationalist group Maharashtra Andhashraddha Nirmulan Samiti (MANS), founded by Narendra Dabolkar began its attempts to convince laypersons that this was not a divine miracle but a natural phenomenon that had a scientific explanation to it. Members of other rationalist groups alleged that this was a coordinated program among the Hindu right to thwart minority groups.

The day after the “miracle” took place, many people reported that Ganesha had stopped drinking the milk. The hysteria died down as quickly as it spread.