I actually use this trick all of the time now and it's actually pretty effective.
A slow blink when looking at a cat signifies that you don't see them as a threat. So it can help relax strange cats, and it is also a cue from the cat that they are okay with you approaching them.
While I understand this comment is made in jest, I do wonder whether cats are able to “map out” or recognize body parts of humans as parts equivalent on the cat body plan.
Anecdotal answer from a cat person: yes. My cat gives me "hugs". He stands on his hind legs on my lap so our hearts are touching and his cheek is against my cheek. It's quite touching. He seems to know what my heart is and what my cheek is, and puts his own versions against mine.
I have always wondered that about eyes in general: I'm not sure if I'm daft or not, but it seems surprising to me that animals with any intelligence look at us in the eyes.
Why fixate on the face and not, say, our hands or body, if they might be afraid of us, to determine if we are a threat? Eyes must provide a higher signal of intent, so it's surprising that even animals on a much lower level of intelligence can read our facial expressions.
It's not a stupid question. It's a matter of stages of engagement.
The face and eyes indicate intention. You can't successfully track or kill without focusing your full attention on the object, and the easiest way to detect this is by seeing where the eyes are focused.
Once a threat is determined, then focus moves to other body parts.
My understanding is, in general, yes. At least major body parts and face parts. Even ones that differ (eg. our ears vs their ears).
Think about it this way how can you kill successfully if you don't have a basic understanding of the anatomy of what you're trying to kill?
I think a general body map is hardwired into more vertebrates. Heads always have eyes, ears and move around. Arms are on the upper torso and legs are at the end of the torso, tails are common.
Beyond that level, your guess is as good as mine though.
Yawning probably goes back at least to the first mammals, it's pretty hard-wired as a standard mammalian social cue signifying a calm and relaxed affect and being in the "rest and digest" parasympathetic mode. It's contagious across species, and even thinking about yawning makes you want to yawn!
Yes but humans have also co-opted it to mean something like “you’re losing my interest,” which seems funny to me. I wonder if there are more examples of instinctive behaviors being deployed sarcastically in humans.
Well, there's of course sarcastic smiling and sarcastic or scornful laughing, the "genuine" forms of both being partly involuntary responses. Another interesting reflex action that's been deployed socially by humans is clearing one's throat to politely request attention.
Absolutely! Dogs use yawning a lot in their communication if you look close enough. They also have other messages like smelling around, looking away, etc. I think they all might mean something along the lines of "I don't see you as a threat to me so we are good"
They're called calming signals, and the reason they're calming is because they make it obvious that the individual isn't "on alert".
If the individual means you harm, they're going to be paying close attention to your every movement since they're about to attack. They'll be staring directly at you, sizing you up, preparing to pounce.
Looking away, smelling around, yawning, slow blinking or eye closing, are all boondoggles that signal, as you said, "hey, I feel at ease with you enough to do this idle busywork, almost as though you weren't here at all because I don't see you as a threat or target".
Cats also regard looking away as a friendly gesture. Which is probably one reason they anecdotally tend to seek out the company of the one person who is allergic or does not like cats. Humans not accustomed to cat body language tend to think of looking away as a sign of aloofness and disinterest instead.
Some people jokingly say that cats are autism and dogs are ADHD and if you know people who are autistic or have ADHD, the parallels are fairly obvious. Autistic people also struggle with other humans insisting on eye contact.
As do Finns (I'm one), and people of many other non-American cultures. And many non-autistic but shy or introverted or highly sensitive persons. You seek eye contact momentarily when you make a point in a conversation, or respond to a point made, or want to empathize, or whatever. Prolonged or too frequent eye contact is weird.
That said, cats very much do stare at your face when they want or are expecting something, usually food. They also have the adoring eyes-half-open stare mode you can see examples of at r/Catsmiring.
I would say that cats better fit the introvert archetype, and dogs the extrovert one, rather than something from the DSM. Anecdotally there's also a significant positive correlation with their respective owners' personalities.
My wife uses this approach with our cat and it works. However, when I try it he pays no attention - could be that I've been his main servant for 18+ years so of course I don't see him as a threat or I have glasses any my wife doesn't or sheer feline contrariness ....
A slow blink when looking at a cat signifies that you don't see them as a threat. So it can help relax strange cats, and it is also a cue from the cat that they are okay with you approaching them.