What's the role in a medievial society for people who are magically bound not to lie?

Question

In the prosperous capital of the country where my story is set, undesired babies are discreetly abandoned in the darkest hours of the night on the front door of the guild of Truthers.

There, as everyone in the city knows, they will be taken care of and raised as guild members, provided that they do not know how to speak when abandoned.

Newcomers are given a potion to drink, the recipe of which is the best guarded secret of the realm, for no member of the guild knows the totality of the long list of steps that goes into its brewing. The effect, however, is known to everyone: for the rest of their lives, whenever they drink that potion again the skin of a Truther will turn permanently blue, if they lie during the next hour.

My questions are the following:

• What role would the Truthers likely occupy in society? Obviously, they would make terrible spies or diplomats, but would powerful people seek their services for other purposes?
• Are they celebrated? Disregarded? Feared?
• Truthers who did lie at some point would obviously lose their advantage. What happens to them?

For the purpose of the question, you may assume the following:

• The effect of the potion is only activated, if the Truther is not telling the truth as best as they know it. Omitting a detail by mistake is not a lie, as long as the intention was to tell the truth.
• Although the potion is complicated to brew, it is not expensive.
• Truthers are marked with the emblem of the guild early on: it is virtually impossible to have someone believe you're a Truther, if you are not one.
• My story is rooted in medieval settings, with moderate magic interventions, but I am interested to know how the response to these question might change through time. Would the Truthers become obsolete at some point and why?
• No known magic can revert the effect of turning blue.

EDIT: What makes an answer better than another?

I am really more interested in the second and third questions (what is Truther's social status? What happens to the blue ones?) than the first. I just think they can not be answered without the first. So an ideal answer elaborates on those points.

Hopefully, the answer would find a plausible balance between the privilege Truthers may acquire but also their weaknesses. Some important points to consider that I have thought have are

• They can not allow themselves to be put in situation where they have to lie.
• If entrusted with secrets, there is always the risk that they will be bound to reveal them in the future.

Perhaps such balance does not exist (i.e. the pros far outweigh the cons or vice versa).

Bonus point for any thoughts on how the answer changes in more modern settings. In a day where we can videotape us and each other, do we really need to pay human witnesses?

Answer 1

Eunuchs formed part of the highest bureaucracy of many Empires (e.g. the Byzantine Empire), occupying positions akin to a Prime Minister for the Emperor. Some parents castrated their sons so they would get a job in the government or become religious patriarchs.

The argument was usually that, since eunuchs couldn't have (natural) children, they would look for the good of the nation and not for their families.

Some of these eunuchs got incredibly wealthy but still they were despised. Most legal systems treated them nor as men or woman and sometimes they were slaves all their lives.

Your Truthers could be the same, trusted public servants of the king/emperor/whatever. The Truthers could be asked any moment about their work without fearing a lie. Imagine the relief a medieval king would have knowing the person managing the Treasury can't cheat him. Or the governor of a province.

The situation of the Truthers might be similar to the eunuchs: envied because they will occupy the highest places in the government, depised because they paid a great price for it. A Truther with the blue face would be seen as a fool who had only one function in life and he didn't fulfill it.

When the society advances, personal forms of government (like Monarchy) turn into groups (Parliaments). A very taxative system of employing workers (the Truthers), who could ask for a lot of money, would be disregarded in favor of a collective control of the government and the development of a press that keeps the public informed about the abuses comitted by that government.

Answer 2

Witnesses. Specifically for legal documents and contracts, or even blood oaths and what have you. As they can not lie, they are the most trustworthy person to use.

Answer 3

Inspectors/auditors. They can't lie about not doing the job fairly, they can't lie about why they're being sent there, they can't lie about what they found, and there's no point threatening them or trying to bribe them because it would be trivial to find out if they were.

Answer 4

There is a gigantic flaw in this scenario.

No one knows the full secret of the potion, so no single person can attest that it has been made correctly. If the potion is made wrong or a fake potion is used, the Truther can say whatever they want and they won't turn blue. So how can anyone know that the potion works, at all, ever? The only way you could completely trust a Truther's statement is if they attest to various things and then lie and turn blue, so that you know they did in fact take the real potion. Which means any Truther is only good for a single use.

Or, you would have to "dispose of" (turn blue) a single Truther to attest the effectiveness of every new batch of potion brewed. But that would only convince the people who were actually there to observe that the Truther:

1. Did not ingest anything for the previous hour;
2. Drank a sample of the potion out of a large container that does not contain subdivisions that might have something other than the potion in them;
3. Attested to various facts;
4. Deliberately told a lie and turned blue.

This would attest (a) the truth of whatever was stated in step 3 above and (b) the potency of the potion batch in that large container.

But if that container were taken out of sight between the public demonstration and any use of the potion, you could no longer trust its potency unless the person taking it also turned blue.

So really, there would be no effective fully trustworthy use of the potion without the Truther turning blue at the end of whatever attestation is made. This drastically changes the social dynamics at play. It also means that Truther services would be extremely expensive, since any Truther's services could only be used a single time. He could attest to many facts in a single hour, but that would be it for life. So this would be a service only paid for by kings or noblemen or such.

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And then, further, they could only attest to facts that they know personally.

So I think every king and nobleman would have a non-blue Truther in their employ, simply to observe everything so the king or nobleman can, in some urgent moment of need, publicly exhibit the Truther and have him take the potion and attest to various things (e.g. to prove the nobleman's innocence in some political intrigue), and then deliberately lie and turn blue.

If the Truther lies too early in the demonstration and turns blue, then the nobleman is out of luck: no other Truther was present to observe the nobleman's activities at the time in question, so no other Truther can attest to his alibi.

Overall, for these reasons, I think the Truthers would only be marginally more useful than a trusted class of priests.

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Blue (discarded) Truthers would be commoners with no special status. They're useless as Truthers at this point.

Actually, there is absolutely no reason why the Guild that makes the potion would ever take it personally. Rather, I think that they would not. It's only one-shot anyway, so why bother?

This also makes it much more convenient to test a batch of potion. Just give some to a prisoner and make him say something false, and then he turns blue so you know the potion is good. And then you can execute him since he was already a condemned prisoner.

Social status of the Guild would be extremely high. Secret knowledge always carries that type of status. (Of course, secret knowledge also eventually blows up in the faces of whoever tried to keep it secret, but that's another subject entirely.)

Social status of someone who takes the truth drug would be nothing special.

Answer 5

Secure Services

The Truthers are the only ones who cannot be spies because they can be given the potion and asked if they are spies. You can also exactly know what their intentions are to their employers... "Are you plotting to kill Lord Richmoney?" Oh, okay, I guess we can trust you then.

They would be valued in any number of professions where trusting another person is difficult. Here are a few examples:

1. Merchant: "Is your markup on your goods less than 25%?", okay, I'll buy from you.
2. Guard: "Have you accepted bribes, or been coerced?", okay, thanks for doing your job well.
3. Maid: "Have you observed your mistress having inappropriate relations?", oh, good my wife has been faithful.
4. Pirate: "Did you take any of the Captain's loot?", there's a good pirate!

The inherent trust that would be given to these truthers would make them very valuable to the people who employ them, and that value will keep the truthers from saying anything that would turn them blue because then they wouldn't be able to have that profession anymore.

Answer 6

They would be put in positions of power where it is hard to check if they have been abusing it.

So the King might hire a truther as for example a steward who oversees a critical project or a far off colony or area. He can then call this steward of the north, honourable lord in service of the King, give him a potion and ask him "well Greg, have you been doing bad stuff behind my back?".

But mainly people like merchants, bookkeepers, policemen, judges, referees and whatever else who might fall for a bribe, coercion or human weaknesses like lust and greed would likely be a truther to make sure they will be found out. If the truther does not have the requisite skills then still no problem as they can be asked to watch precedings and be in the presence of people that need to be kept an eye on, so they can still be asked questions about the others doings without being able to lie.

Anyone with a blue skin would be a pariah. They had something they risked getting blue for and outright lied for, or they might not have known they had gotten a drink and lied, something a truther should not do anyway. Although most would likely be punished if not executed after they are found out.

Answer 7

They would be negotiators.

The potion would be used at or towards the end of a negotiating session but before any of the parties have signed anything. To prove that the negotiator did not hide anything, is not being paid by one of the parties (aside from the fees all parties pay), and has no hidden agenda. To her/his knowledge, the contract/treaty/etc is the very best compromise for all parties.

People will respect them for being important officials who get paid well and do their job honorably. But unless that's an exception in your world, it won't really change their social status. No one outside the guild can get the drink (and even if they could, they'd never know if it was the real drink so it couldn't be trusted) and no one can force the truther to speak during that hour. So there's no real use for this other than for their job and occasionally if needed to testify in court or go before the ruler.

Blue-skinned truthers would of course lose their jobs (since they can't turn extra blue if they lie again later) and all the social status that goes with it. Just like anyone who really messes up, their spouses might leave them, their kids won't respect them, their parents might disown them. Or not. They will lose some friends. They will take a normal job without such high stakes work. And they'll settle into their new (lower-paid) reality.

Answer 8

Lawyers

Provided your system of laws has an emphasis on finding the truth, it will be critically important to have a group of people who can be counted on to debate a case honestly, without fear or favor, representing each side to the best of their ability. If the "turning blue" also applies to hyperbole or rhetoric, even better. Knowing that they can't be bribed, intimidated, or otherwise coerced is already a big improvement on the real world. You might not even need a jury, since the judge is guaranteed to be impartial.

This will give them significant social status, much like lawyers in our world, as they will effectively be the arbiters of truth and justice. This is a lot of soft power. However, the impartiality requirement will keep them from exercising it much, especially as they will have to answer the standard "have you ever abused your position" at the start of each case, which means they can't directly do much.

This also means they won't all become hugely rich; because they have to be impartial and honest, this means there will be much less difference between them than lawyers in RL, to the point that they might even wear a mask during trials, because the focus is on the truth not the speaker. I can see this becoming a major cultural ritual.

Truthers who turn blue will have all of this social pressure turned against them. Ostracised, maybe even banished or killed, because they will have acted against society as a whole, and abused the trust of the community. There will be enormous stigma against them.

Answer 9

Advisers

A person who is an adviser is supposed to judge things according to their best knowledge. Concealing anything undermines the sense of having an adviser but that's what happened ever to often in reality. People are afraid for various reasons (usually due to the power held by the one who asks - a king, , company manager etc.) to oppose someone in power. The Truthers risk more by lying since they'll lose everything they have - their ability and thus position (and as a result also money for living). I guess most people (at least in broadly understood European/Western culture countries) know the tale "The Emperor's New Clothes" by Hans Christian Andersen. The problem existed in past and still exists. Having a critic who is bound to tell the truth can give a totally unbiased second opinion - something of value hard to estimate.

Are they celebrated? Disregarded? Feared?

Well, I would say it will be a mix of reverence and fear. They bring a lot of value being source of reverence. But we fear truth. That's why people won't become Truthers voluntarily (not to mention potion price - see below).

Truthers who did lie at some point would obviously lose their advantage. What happens to them?

They will lose their status for sure as already explained above. Yet they might become useful for the guild. Since now they can lie, they may be granted access to the secret of potion brewing (of course part only). Of course not all and large part will know only the disguise version so that no-one can know for sure if the guild member knows the real part of recipe or a fake one. The member themselves won't know if they know a real or false recipe and will on many occasions take part in "brewing".

It might be that the actual brewers will lie voluntarily on a guild's request but only those innermost guild members will know this.

Would the Truthers become obsolete at some point and why?

No. On the contrary their service will be more and more sought. The second unbiased opinion is as valuable today as it was always but there are more areas in which you need them.

Side note

Although the potion is complicated to brew, it is not expensive

It may not be expensive to brew but since it is so secret and so useful it will be for sure expensive to buy. This way the Truthers' guild, which corners the market of the potion will be one of the wealthiest guilds.

Answer 10

undesired babies are discreetly abandoned in the darkest hours of the night on the front door of the guild of Truthers.

There, as everyone in the city knows, they will be taken care of and raised as guild members, provided that they do not know how to speak when abandoned.

Newcomers are given a potion to drink, the recipe of which is the best guarded secret of the realm, for no member of the guild knows the totality of the long list of steps that goes into its brewing. The effect, however, is known to everyone: for the rest of their lives, whenever they drink that potion again the skin of a Truther will turn permanently blue if they lie during the next hour.

If the guild/realm holds the secrets for this potion, then any pronouncement by a truther requires trusting the people that prepared/provided the potion. All the people. And those who handled it after its preparation (although that can be mitigated by wax seals on the bottles). So any usage of such a potion would need everyone involved in the process to also be truthers and swear under its influence that they had prepared their portion/step correctly, and a truther who actually knows all the steps (or at least all the other truthers involved with the steps) to confirm that all the truthers swearing to the fact that their steps were correct are really all the people involved in its production. (Even that doesn't fully cut out sabotage, since it would allow an unknown infiltrator to potentially muddle the mixture without the knowledge of anyone involved.)

I recommend a two-potion system, where the first potion (which converts someone into a truther) is a carefully guarded secret, and the truther guildmaster annually swears publicly that it is compounded properly (as far as they know) under the influence of the second potion, which is just blueberries or something which can be easily obtained, but makes tampering obvious.

It still doesn't rule out sabotage or someone spiking a truther's drink with it (and would lead to truthers avoiding certain foods unless they were on the job), but it reduces the high amount of trust everyone would need in the truther's guild.

What role do the Truthers would likely occupy in society? Obviously they would make terrible spies or diplomats, but would powerful people seek their services for other purposes?

Are they celebrated? Disregarded? Feared?

Anyone who wants a verbal/witnessed contract made needs a truther on hand, so that nobody can say afterward "I was coerced into it!" or "my seal was stolen from me and put on that contract!" However, that truther needs to be kept 'pure' afterward by the interested parties. If a truther is a witness/notary for John Doe, John Doe really won't want that truther potentially going blue (by lying about a different incident/contract) as long as that truther's information would be necessary for him to prove. So for any John Doe that has a truther witness, it's within their best interests to keep that truther from witnessing any other cases/contracts/etc.

Because once that truther goes blue, the 'absolutely truthful' evidence John Doe was counting on disappears, since the truther can no longer be presumed truthful.

And anyone could spike a truther's drink with the potion, without their knowledge, and they might say a lie in the hour after that and go blue, rendering anything they'd witnessed worthless as evidence. So it would make sense to keep truthers who had witnessed something important under protective custody and heavy guard.

Truthers who did lie at some point would obviously lose their advantage. What happens to them?

Hopefully they can become regular commoner members of society, depending on the world. If everyone knows they were abandoned kids (so they didn't choose that life for themselves), while "so how'd you go blue?" is a reasonable question, it's not as if they are a cast-out noble or scholar or someone who worked their way up and threw everything out the window for a reason.

I think general populace feelings would be mixed about them.

I doubt commoners would encounter many non-blue truthers in their daily lives in the first place.

And if a truther was involved in an important deal, or was privy to secret information, I doubt they would get out alive after their usefulness expired by going blue, since the other info they have would still be valuable, even if unconfirmed.