What should you do if you belatedly find out you've fed someone something they shouldn't/wouldn't eat?

No, but if you’re making a decision (such as telling after-the-fact) you should take their beliefs into consideration when determining what counts as good or bad for them. What you described above discounts the possibility of religious or spiritual harm to them from their eating prohibited food, because you don’t personally believe in such harm for you. That is not respectful.

~Max

Why? I have clearly stated that don’t believe it makes any difference at all if I don’t tell them. It as if it never happened. Why don’t you respect that belief?

I edited “have to” and it now reads “should”. The “you” in that sentence is generic and I was describing my own concept of respect. Please substitute:

If I’m making a decision (such as telling after-the-fact), I take their beliefs into consideration when determining what counts as good or bad for them.

I don’t have to believe there is a difference, but I do defer to their beliefs as to what they consider helpful or harmful to themselves as a matter of respect, which respect you evidently do not share.

~Max

I don’t know about the theological underpinning of the rules of halal. But the kosher rules don’t say, “it’s a sin to eat pork”, they say, “pork is unclean to you”.

What would you do if you accidentally included shit in the dish? (Make up whatever back story you want to explain how that came to happen.) That’s what you should do if you accidentally feed non-kosher food to someone who keeps kosher.

In general, i wouldn’t tell them. But in this case, where the kid is liable to be similarly careless about explaining his dietary prohibitions to other people, i would tell someone. Maybe the kid, maybe one of his parents. It would depend on a lot of details including the age and general maturity of the kid and my relationships with the various parties.

Also, this story illustrates why many people with dietary restrictions don’t eat in other people’s homes. Because people who don’t follow those dietary restrictions don’t get it, and are apt to make mistakes. Many people with dietary restrictions are more trusting of people with different dietary restrictions than of people with no dietary restrictions, because those people at least “get” the general idea.

How am I to know that this is your belief? I would know that you believe you cannot eat certain foods. How do I know your belief extends to me telling you that you have unintentionally eaten a food you consider forbidden? Whether it’s a religious belief or personal I don’t expect that everyone wants to be told if this happened. I don’t think I recall anyone saying that about their belief based dietary restrictions.

So, are you talking about a religious belief that you must be told about this matter, or a personal one? In either case did you tell this to me beforehand? Do you think that everyone else shares this belief or even knows that you do?

What? How could my belief about me extend to you telling me something?

ETA: Say I keep kosher, I eat a meal at your house that isn’t kosher, and then it comes out that I thought the meal was kosher. You have to decide whether to tell me or not. Since you decide based on a harm analysis the question is whether telling me would do more harm than not telling. But what counts as harming me? Is it up to you and your beliefs on what constitutes harm? Is it up to me and my beliefs? I say if you respect me, you will not presume based on your ignorance of my religious beliefs (or personal disagreement with them, if known) that I won’t suffer any harm if you keep quiet.

~Max

It is up to me and my beliefs when I act or don’t act. If I know that is your belief then I may tell you. But I’m unlikely to know this is your belief unless you’ve told me.

Now tell me, how many times have you told people that your want to be informed if you unintentionally consume proscribed food. How many people have told that to you?

If it’s an allergy, or some other sensitivity, or it is a vegetarian who hasn’t eaten animal proteins in years, you should tell the person. There may be health consequences and they are better prepared to deal with those if they know what they’ve eaten.

I think the default, if you don’t know the basis for the food issue, should be to tell them.

Every single time I go out to eat, for the record.

~Max

I think that means you recognize this is not something everybody would assume.

I’m confused what exactly you want me to admit. The scenario is that you belatedly find out you’ve fed someone something they shouldn’t or wouldn’t eat. People with dietary restrictions are supposed to tell people beforehand so it doesn’t happen in the first place and there is no confusion in the event of a screw-up.

Specifically, to prevent this:

~Max

It’s ultimately up to you but, if you respected me and my beliefs (assuming I kept kosher or some other religious restriction), you would defer to my beliefs on what I consider harmful to myself. And if you don’t know my beliefs on that, given that I have the religious dietary restriction and you don’t, you wouldn’t presume my beliefs on the subject match yours.

~Max

They are supposed to tell people what their restrictions are. Telling them they have to tell you later on if you did eat something outside of those restrictions is not usually done. I’m not talking about you being half way through a pork chop and telling you when I find out you thought it was lamb. I’m talking about later on, after the fact when nothing else can be done about the matter, there is no longer any concern of continued violations.

When the subject is telling you after the fact I wouldn’t presume that at all. Wanting to be told after the fact is not the same thing as maintaining a Kosher or Halal diet.

My actual dietary restriction is a food allergy, not a religious one, and the concern of an allergic reaction does not disappear just because I’ve finished eating the food. Reactions can occur up to 48 hours later, for example in my sleep after I’ve gone home.

~Max

The OP detailed a situation where the person with the dietary restrictions told a friend who failed to inform the actual chef, so there was intent to keep the restrictions for this meal.

~Max

I have already ruled out medical concerns. We’re talking about a belief.

But then you asked how many times I told people of my want to be informed if I unintentionally consume proscribed food. I answered. And the actual circumstances there are medical.

My whole argument is that by treating medical harm as real and disregarding religious harm entirely, you are being disrespectful to the guest.

~Max

Seemed we were talking about religious beliefs, not medical. I think I made that clear in our conversation.

Well, since I don’t have a religious dietary restriction, I’ve never made any requests about one. And in the scenarios related to this topic, you wouldn’t hear such a request. Were there any other questions you wanted to ask about me or my position?

~Max

I disregard your unknown belief in religious harm after the fact, whether from eating the religiously proscribed food or a religious belief that you must be told had that happened after the fact. Perhaps you are still a good person and I still respect the rest of your beliefs that I know about. I usually pay more attention to actual behavior instead of beliefs.