* Reading this post again myself, I found that what I wrote in this post is very confused. So I partly rewrote this post.

Today, I watched a (clip of) YouTube video, in which Toshio Okada argues concerning the question, What is the essence of laugh? In the argument, he draws upon a notion put forth in a novel by Robert A. Heinlein.

According to the video, the notion is this: laugh is all about either an attack or an attack turned inside out. (This diary is an English diary, so I'm writing in English. In the video, Toshio Okada talked in Japanese. So here I may be making his words somewhat distorted by using English.)

As of now, I have not checked what Heinlein really wrote in his novel, the original text.

Anyway, in the video, Toshio Okada said that he has come to be quite convinced by the notion about laugh put forth by Heinlein.

By the way, In Japanese, smile ("微笑む") and laugh (can indicate "洪笑", "失笑") is not always be distinguished, as we use the word "笑う" for denoting both. Was it the latter, not the former, that Heinlein dealt with as a subject in the novel? I don't know for sure in what intention the novel was written. I've not read the novel in question.

But the subtlety concealed in the novel might perhaps be in that the notion implies that smile and laugh might be on the same continuous spectrum, with the former being a somewhat attenuated form of the latter. That is, readers might be prompted to ask this: Are the two essentially of the same kind? Or can't they be distinguished by some different factor?

Being a short clip, it's a bit unclear whether or not Toshio Okada generalized what applies to laughing to smiling. (Probably not. For according to information I found in comments below the video, it seems that he mentioned something related to a difference of smile and laugh elsewhere.)

Anyway, watching the video, I personally had to think of whether such a generalization is overapplication or not: Can smile and laugh be treated the same way? These two things seemingly share some traits in its facial expression to some extent and there might lie some complex relation ... However, smile is something serene. And it could be expressed as something bright and cheerful depending on context. Nevertheless, can it be possible that it's basically about attack or reaction of attack, or the like? It's an idea that makes you feel uneasy...

Contempt or intimidation can be a factor of laugh. It's, yes, aggressive. But can such be a factor of smile too?

I made a consideration about this problem ... and the idea I've come up with was this. That is, I suspect that it would be more appropriate to say that smile comes from relief, rather than attack; laugh occurs when aggressive reaction or emotion is joined to relief.

Let's take examples. You would make a smile when you find youself being in a safe zone. Or when you feel fun or happy with friends so that you feel very relieved knowing that you're in so nice a condition, on your face smile or trace of smile would appear. Likewise, you would expect to see smile if one is in a peaceful state of mind relieved from fear. Or derivatively, you would make a countenance of smile when you're trying to relieve or console a crying child. For it's the sign that there's nothing worrisome or horrifying.

And, on the other hand, consider when you see something appalling or extremely unusual or odd on TV for example, which presents the image of menace (an attack in a wider sense) to human instinctive reactional inner circuits. (The circuits for survival which might possibly automatically construe the unusual as the potentially dangerous, I'm hypothesizing here). You'd immediately recognize that it's just a TV show. After suddenly startled, the tenision is abruptly disappear, and then you're aware that you're safe. This instant turn from tension to relief might be the cause of your laughing out.

Or when something very foolish is shown or in sight, you might laugh. It is thought that you feel relief thinking that you're superior to what you're looking at or that you're contrastingly sound and sane, and that that positionality is sure and firm. That is, you unconsciously get the idea that you're on a superior echelon. You're relieved that you're not on par with the negatively seen. And when contempt enters, the laugh would rise.

And derivatively, when you're trying to intimidate, challenge, or mentally deal a blow to your opponent, you may laugh. It's a purpusefully displayed sign that you're thinking you are powerful and mighter than your opponent, though it might be a mere camouflage. Or you may laugh in order that you be not demoralized in front of menace, that is, as a self-encouragement. In the weakest version of spiteful challenge, that may perhaps take a form of charming banter. In this case, it might take on a form of something like a style of manly mind boxing exercise, so to say.

Seeing these examples, it seems to me that it's unlikely that smile and laugh are both based on some form of attack or aggressive intent.