The eight additional "weighty rules" for nuns (garu-dhammas or Sanskrit guru-dharmas) are implausible. Buddhism was the first world-religion to ordain nuns. But the inherently unequal rules the Buddha allegedly imposed on women as a precondition for allowing them to ordain as Buddhist nuns are in dispute.
The first Buddhist nun was the Buddha's adoptive mother, Mahapajapati Gotami. She is said to have gratefully accepted the extra rules. Yet, elsewhere she comes to the Buddha to ask a question that, had these rules indeed been laid down as a precondition, would have been perfectly clear. What seems more likely is that Buddhist monks, fearing a challenge to their status, instituted these rules based on the underlying assumptions about the inferiority of women prevalent at the time.
The intention behind the extra rules is commonly said to have been to place nuns in an inferior position to monks. A kinder explanation is that they were intended as a safeguard for women living in vulnerable situations.
But a more recent study examining the relevant texts -- brought to light by the senior most Western Buddhist nun Ven. Tathaaloka (seen in the video) -- is that these rules could not have been laid down by the Buddha as claimed.
The additional rules are listed in the Cullavagga as follows:
- A nun must always show deference to monks by, for example, bowing even to the most junior.
- A nun should not spend the rains-retreat in a place where there are no monks.
- Lunar observances should be led by a monk not a nun.
- At the end of the rains-retreat a nun must appear before both the assemblies (Sanghas) of monks and nuns to report on any suspected or actual breaches of the disciplinary rules.
- If a nun commits a serious offense she must undergo expiation before both assemblies.
- After her two-year training period as a novice (śrāmaṇerī) is complete, a nun wishing higher ordination must obtain it from both assemblies.
- A nun must never offend or insult a monk.
- A nun must never admonish a monk, but a monk may admonish a nun.