This seems widely circulated. I've seen it intended as a serious text:

In ancient Greece (469 - 399 BC), Socrates was widely lauded for his wisdom.
One day an acquaintance ran up to him excitedly and said, "Socrates, do you know what I just heard about Diogenes?"
"Wait a moment," Socrates replied, "Before you tell me I'd like you to pass a little test. It's called the Triple Filter Test."

'Triple filter?" asked the acquaintance."That's right," Socrates continued, "Before you talk to me about Diogenes let's take a moment to filter what you're going to say. The first filter is Truth. Have you made absolutely sure that what you are about to tell me is true?" "No," the man said, "Actually I just heard about it."

"All right," said Socrates, "So you don't really know if it's true or not. Now let's try the second filter, the filter of Goodness. Is what you are about to tell me about Diogenes something good?"
"No, on the contrary..."

"So," Socrates continued, "You want to tell me something about Diogenes that may be bad, even though you're not certain it's true?" The man shrugged, a little embarrassed.

Socrates continued, "You may still pass the test though, because there is a third filter, the filter of Usefulness. Is what you want to tell me about Diogenes going to be useful to me?"
"No, not really."

"Well," concluded Socrates, "If what you want to tell me is neither True nor Good nor even useful, why tell it to me or anyone at all?"

The man was bewildered and ashamed. This is an example of why Socrates was a great philosopher and held in such high esteem.

Some variants add this twist below, but let's not analyze that.

It also explains why Socrates never found out that Diogenes was having an affair with his wife.

Source: Speaking Tree

Did this story come from the most reputable historical sources (the same students who transcribed Socrates's speeches/anecdotes) or is it a fabrication or adaptation from another story?

  • Do you want to check the anecdote or to find where this story comes from (as you ask in the question)?
    – Common Guy
    Commented Oct 27, 2017 at 10:38
  • To check the anecdote, firstly. Finding the original source would be my favourite means! Commented Oct 27, 2017 at 10:59

4 Answers 4


edit: See Jacinto's answer below

This was originally an aphorism by a Protestant missionary named Amy Carmichael, who penned it while bedridden in India in the 1930s and 40s.

Perhaps these three sieves will help to keep some words from being spoken that would grieve the Spirit of love and hurt someone whom our Lord loves. Is it true? Is it kind? Is it necessary?

Amy Carmichael, Edges of His Ways (Fort Washington: Christian Literature Crusade, 1955)

The reattribution to Socrates seems to date to around 2003, originally circulated via email.


As ChrisW's answer and comments to it attest, this teaching is also found in the Indian Manusmriti:

सत्यं ब्रूयात् प्रियं ब्रूयात् न ब्रूयात् सत्यमप्रियम् प्रियञ्च नानृतं ब्रूयात् एष धर्मस्सनातनः

  • मनुस्मृति

Speak the truth, speak favorably, do not tell the truth that is not favorable. Also, do not tell untruth that is favorable - this is the eternal religion.

The Manusmriti was actively being read in India in the 1950s, so it could have been an inspiration to Carmichael. ChrisW quotes the Abhaya Sutta; I am not sure that this was being read in India at that time, but it's certainly possible.

  • Could you find when it was attributed to Islamic philosophers, like in Denis's comment? Commented Oct 29, 2017 at 18:52
  • 1
    @aitchnyu I could not date that to earlier than 2016. Arabic versions available online seem to be translations of the English chain mail about Socrates, and all were posted in 2017.
    – Avery
    Commented Oct 30, 2017 at 1:50
  • 1
    Avery, the three-sieves maxim appeared in many children and religious books from 1845 on in the UK, and a version involving Socrates has been around at least since 1977.
    – Jacinto
    Commented Aug 4, 2022 at 23:17

To complement Avery’s answer, the three-sieves maxim has been around at least since the mid-1800s. It appears in Rev. Charles B. Tayler, Lady Mary or Not of the World (London, 1845, p. 205):

      “But perhaps we ought to think of the three sieves, before we allow ourselves to speak of others,” observed the Bishop.
      “And what is that story?” said Mr. Arden.
      “It is not a story!” he replied, “but a maxim, which all will do well to attend to when they speak of those that are absent. The maxim is this, that before we allow ourselves to find fault with any one behind his back, we should ask ourselves three questions. The first, ‘Is it true?’ The second, ‘Is it kind?’ The third, ‘Is it necessary?’”

It then keeps reappearing in various books and magazines until the present day. For the first ninety years, all that I saw are fictional stories, and none makes any reference to Socrates or any real person. Until 1936 when you find the now familiar dialogue between Socrates and his gossipy friend. It is presented as a Catholic anecdote in The Liguorian (Redemptorist Fathers, Oconomowac, Wisconsinn, July 1936, p. 363):

      To the life of Socrates is attributed this legend by the Franciscan Herald. One day there came to this wise philosopher, a busybody who said:
      “Have you heard, O Socrates ―”
      “Just a moment, friend,” said the sage, “have you sifted what you are going to tell me through the three sieves?
      “Very well, then. Since what you have come to tell me about the case is neither true, nor good, nor needful, let us forget about it.

I wasn’t able to track the Franciscan Herald. Some later authors when recounting the story are careful enough to present it as an “anonymous anecdote” (Tony Castle, Quotations for all occasions, 1989, or Jo Ann Larsen, The heart of goodness, 1999). And in 1995, Thomas Hale (On Being a Missionary) presents the maxim as a Muslim proverb:

In all this, even Christians will do well to remember the three sieves of the Muslim proverb as they choose what they will say: Is it true? Is it kind? Is it necessary? Before we speak, let our words pass through all three sieves.

So after all this, my view, for all it’s worth, is that the involvement of Socrates in the anecdote is fiction; a late addition to an existing story; and if anyone claims it is based on ancient sources then the onus is on them to tell the rest of us what those sources are.

  • 5
    The number of Ancient Greek sources is also very limited. It’s not in Plato, Xenophon, or Diogenes Laertius. This exhausts all the contemporary sources and the biggest secondary historical source of information about Socrates. Source: I’ve read them.
    – Shamshiel
    Commented Aug 5, 2022 at 0:38
  • It's interesting that multiple people call this a Muslim proverb, because it does describe basic injunctions against backbiting, but I've never heard them joined together as proverb.
    – Avery
    Commented Aug 5, 2022 at 13:11
  • @Avery, I'm wondering whether there is such a Muslim proverb. A reference to it appears quite late in the storyline anyway. Found an earlier, 1936, Socrates version; updated my answer. I'm now thinking, this story was so ubiquitous in English-speaking countries, an especially in Christian publications, that's probably where Amy Carmichael got it from.
    – Jacinto
    Commented Aug 6, 2022 at 11:32

As a counter-point to Avery's answer I wonder whether the aphorism has earlier, Buddhist origins.

Right Speech

The criteria for deciding what is worth saying:

[1] "In the case of words that the Tathagata knows to be unfactual, untrue, unbeneficial (or: not connected with the goal), unendearing & disagreeable to others, he does not say them.

[2] "In the case of words that the Tathagata knows to be factual, true, unbeneficial, unendearing & disagreeable to others, he does not say them.

[3] "In the case of words that the Tathagata knows to be factual, true, beneficial, but unendearing & disagreeable to others, he has a sense of the proper time for saying them.

[4] "In the case of words that the Tathagata knows to be unfactual, untrue, unbeneficial, but endearing & agreeable to others, he does not say them.

[5] "In the case of words that the Tathagata knows to be factual, true, unbeneficial, but endearing & agreeable to others, he does not say them.

[6] "In the case of words that the Tathagata knows to be factual, true, beneficial, and endearing & agreeable to others, he has a sense of the proper time for saying them. Why is that? Because the Tathagata has sympathy for living beings."

— MN 58

This has three sieves which are nearly the same as quoted in the OP:

  1. True
  2. Good and useful ("beneficial")
  3. ("endearing and agreeable")

I think that the historicity of the Pali suttas are fairly well established (i.e. they're certainly not modern) -- originally transmitted orally, this batch codified 3rd century BCE - 2nd century CE.

The Buddha was maybe a contemporary of Socrates (maybe both died around 400 BC, see here and here), though in different places (approx 5000 km apart).

Alexander the Great died later, in 323 BC (after reaching India); and the Stoics were founded a little after that, in the early 3rd century BC -- which is about the same time as when emperor Ashoka created a Buddhist empire and sent Buddhist missionaries (not to mention traders) to the Mediterranean -- some people think that Stoics (even if not Socrates) may have been influenced by Buddhism.

This version would be earlier than the Islamic philosopher Saadi (who was mentioned in the comments) too.

  • The real question is, how many Buddhists were actually reading the Abhaya Sutta after 300 AD or so? (As opposed to chanting the untranslated Pali in ritual settings. Also, I'm being a bit tongue in cheek)
    – Avery
    Commented Nov 1, 2017 at 23:05
  • I imagine it (as "right speech", part of the "virtue" branch of the threefold training) was told via Dhamma-talks to Buddhist laypeople (I also guess that e.g. Europeans knew at least a little Christian doctrine, even when the Church's language was Latin rather than vernacular). Also (though I don't know whether this is true), see Greco-Buddhism -- Philosophical influences. Some people must have been interested in philosophy!
    – ChrisW
    Commented Nov 1, 2017 at 23:25
  • 1
    Hmm, there is an [arunachala-ramana.org/forum/… scripture) that deals with truth and kindness. I guess Amy Carmichael's story shows she absorbed Indian philosophy during her stay. Commented Nov 2, 2017 at 10:41
  • @aitchnyu Thank you, I didn't notice she was bedridden in India. I don't remember any ordinary Christian scripture that so closely matches these filters. Actually I see the version which you quoted has two filters (it says that speech must be true and pleasant). That's slightly different from the Buddha's version quoted above (which says that speech must be true and beneficial, and may be pleasant or unpleasant but should be said at the proper time and with sympathy).
    – ChrisW
    Commented Nov 2, 2017 at 12:32
  • @ChrisW I believe softening the blow of saying unpleasant facts/news is a big thing here in India. I believe there must be more scriptures and lectures on this subject, from which she created this story. Commented Nov 3, 2017 at 12:47

This seems uncharacteristic of Socrates. From what I remember having read many of the Socratic dialogues, the character of Socrates was as someone focused on finding truth and expelling untruth. Socrates would say there is no such thing as an unuseful truth, or a useful untruth; spreading untruth is misinforming people, which is harmful, and thus is never useful. Conversely, one must, in order to contribute to the general understanding of the world in which one lives, always speak the truth and spread knowledge, when knowledge is what one has (Socrates had a very specific definition of knowledge, which is a completely separate discussion, but if one has knowledge, it would be one's responsibility to make sure others also have that knowledge), irrespective of whether or not that knowledge is "good".

In fact, Socrates was executed for spreading "ungood" truths; the Socratic Dialogues (with the exception of the Phaedo, amongst the ones I've read) all share the central theme whereby Socrates talks to someone who claims to be some sort of expert or bigwig and telling them exactly how stupid they are and how much they don't know, and the Apology discusses how stupid of an idea it is to execute someone for telling truth to power. The Crito discusses specifically the dissonance between saying what one knows to be true at all costs, and saying false statements that are "good" (socially acceptable).

I can't believe that this is something that Socrates would say, it doesn't seem characteristic of him.

EDIT: Doing some cursory wiki-diving on the Socratic Dialogues, I found this, which might be interesting:


In Hippias Major, Socrates attempts (of course, unsuccessfully, as in all the Socratic Dialogues) to define "beauty". Two of the four definitions that Socrates provides are "the useful" and "the favourable". However, again, Socrates did not believe that only that which is "beautiful" is worthwhile to be said; there are plenty of things which he said which were not "beautiful", so this is also not the answer.

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