Why monks filter water? What about microorganisms?

As modern people who know about microorganisms, what actions should we take additionally?

In case we already know or doubt that a group of microorganisms are sentient, what should we do about them?

Anyone here got an image that monks start to have to carry a microscope with them as among the requisites? :crazy_face:

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Can we ignore other very tiny beings in the same way we do to microorganisms? Is there a minimum body size?

Well, I guess that such a criteria as “living being that can be seen by naked eyes” is a reasonable rule to follow for monks, no? Or maybe something as a guide as lines on the palm?

Otherwise, you will have to wait for comments from experts in Vinaya as Bhikkhu @Brahmali

I have also heard about this criteria used by some people. Is it backed by texts (at least implicitly)?

It’s in the Chinese Vinaya Bu-Pc 52. I am not sure if there is an equivalent in Pali version or in Pali commentary.


Here too: Is there such mention in the Sutta about Microbes being predicted by the Buddha? - Discussion - Discuss & Discover (suttacentral.net)

Boil water or filter until no more microbes, for the sake of health. It’s basically wisdom passed down from the time of diseases spread via unclean water.

It is distressing to find visible living beings (mosquito larvea) in your water supply. I had this problem for 3 months at my kuti. They would come rushing out the tap in quite a shock that they had been brought into daylight. It turned washing my alms bowl into a 40 minute endeavour while I filtered and rinsed and peered.

There are two rules related to water and little critters.
Bhikkhu Pacittiya 20 and Bhikkhu Pacittiya 62 The Bhikkhuni’s have the same rules with different numbers.


If this is really all out of concern of the welfare of living beings, what happens with the filter and living being in it? Are there rules regarding how one has to treat the filter?

No there are not. (Someone please correct me if there are.) Those days it would have been a simple cloth filter. Remember this is for filtering visible organisms. I would assume that it was understood that you would simply rinse the cloth when you were done simply as a matter of keeping things clean.


Does that mean one does not really protect the lifes of the visible organism? They still die while rinsing the cloth?

“If anyone were to say that just as a person does a deed, so is his experience is determined by it, and if this were true, then living the holy life would not be possible, there would be no opportunity for the overcoming of suffering. But if anyone were to say that a person does a deed that is to be experienced, so does he experience it, then living the holy life would be possible, there would be an opportunity for the ending of suffering. For instance, a small evil deed done by one person may be experienced here in this life or perhaps not at all. Now, what sort of person commits a small evil that takes him to hell? Take a person who is careless in the development of body, speech and mind. He has not developed wisdom, he is insignificant, he has not developed himself, his life is restricted, and he is miserable. Even a small evil deed may bring such a person to hell. Now, take the person who is careful in development of body, speech and mind, He has developed wisdom, he is not insignificant, he has developed himself, his life is unrestricted and he is immeasurable. For such a person, a small evil deed may be experienced here or perhaps not at all. Suppose someone throws a grain of salt into a little cup of water. That water would be undrinkable. And why? Because the amount of water is small. Now, suppose throws a grain salt in River Ganges. That water would not be undrinkable. And why? Because the amount of water is great”

Why would they? you would just turn it inside out and rinse it in whatever body of water they came from.

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Oke, then it is oke :innocent:

This video is relevant to the discussion here, despite however not providing a specific answer to the matter:


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Is it needed to rinse the cloth into something like a pond or stream?
If not, what will happen to the beings in the cloth, who can live only in the water?

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This rule comes to mind, as a result of a monk dying of thirst after he got in a fight with his travelling companion and didn’t have his own water filter!

This will affect people’s confidence …” after rebuking him … the Buddha gave a teaching and addressed the monks:

“If you’re traveling with a monk and he asks to borrow your water filter, you should lend it. If you don’t, you commit an offense of wrong conduct. But you should not travel without a water filter. If you do, you commit an offense of wrong conduct. If there is no water filter or strainer, you should determine a corner of your robe: ‘I’ll drink after filtering with this.’”


So we still have to carry them around when going out? Even for like house dana? When there’s basically no chance to use in countries with ready access of clean water?

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Just determine the corner of your robe and you will be fine. But no, there is no exception. Best to consult with your teacher and do as they suggest.


Even more difficult if you actually have something you use and determine for filtering water inside the monastery (as in my case). What if it’s wet?
I can’t bring myself to determine my actual water strainer as requisite cloth and the corner of my robe as a water strainer :thinking:

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