@gorblax asked: If you were the last man on Earth, would you still be beholden to the halachot of ma’arit ayin?
For those of you who aren’t familiar, ma’arit ayin (מראית עין) is a principle that means that you cannot do something that looks like it is going against halacha, even if it is technically permitted. So, for example, in my vampire post (here), I mentioned that a vampire could appear to be drinking animal blood when they are in fact drinking human blood. Since animal blood is prohibited in a way that human blood is not, that could pose issues for a vampire who wants to keep kosher.
I fully expected the answer to “if there was no one around, would ma’arit ayin still apply” to be “of course not,” but I looked into it a bit further to be sure, and it seems like the answer is actually “it’s complicated.” (Credit to
Mi Yodeya for making me realize this complexity - specifically
this answer and
this answer.)
There is a principle that “כל מקום שאסרו חכמים מפני מראית העין - אפילו בחדרי חדרים אסור,” “everything that the sages forbid because of ma’arit ayin - even in the most hidden of rooms is forbidden.” You can find this expressed in several places in Gemara, for example
Shabbat 64b and
Beitza 9a, and is expressed in later halachic texts such as the Shulchan Aruch as well. I’ll assume that “literally no one else is around anymore” applies to “most hidden of rooms,” since in both cases no one can see you.
However, that principle is debated. At the very least, it applies to d’oraita (literally “from the Torah” as opposed to “from the rabbis” but it’s a little complicated) commandments, when it appears that you are doing something actually forbidden. It may not apply to rabbinic commandments, or when you’re doing something permitted that merely appears forbidden to outsiders (see commentary on Beitza 9a in the link above).
According to
the Mishna Berura, as far as I can tell, the principle applies to matters where the prohibition that it looks like you are doing is a prohibition d’oraita, and not to matters where the prohibition that it looks like you are transgressing is a prohibition d’rabanan, a rabbinic prohibition.
TL;DR: if you were the last man on Earth, would you still be
beholden to the halachot of ma’arit ayin? Probably some of them, but not
all of them.
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