user2259: In sanghas following the tradition of Zen Master Thich Nhat Hanh, to show appreciation one does not clap, instead one flaps his/her hands. This silent visual applause is similar to the sign for applauds in American, British, French and possibly other sign languages used by deaf persons.
Which other buddhist traditions also use silent visual applause to show appreciation? What is the origin of this way of showing appreciation in buddhism, was it borrowed from a sign language, and if so where and when?

user254: This video says that it's widespread among French and German university students, ecologists, especially left-wing, for example at political assemblies and unions. And it says that an internet search shows that it's part of the "language of signs" but that no-one knows which country it began in.
The page Monks and nuns from the Thich Nhat Hanh collective, in Plum Village, France, pay our school a special visit suggest that Thich Nhat Hahn are:

From France
Teaching 'silent applause'
Teaching 'ecologist' songs such as "I love nature"

So perhaps they adopted the gesture from that milieu (or vice versa): i.e. from European students and young ecologists.

user811: The Sound of One Hand = "quiet sound" (Soundless Sound - Emptiness) 
At some point, completely quiet heart that does not even sound that can make us being distracted. Ears are hearing is still heard, but absolutely not disturbed mind. It is "beyond" all sound.
That is, in silence we "hear", "see", "understands" or "enlightenment" is many things, but when the mind is being distracted because of the "noise" we do not hear, do not see, do not understand.
The Sound of One Hand (101 storie Zen -Nyogen Senzaki)
The master of Kennin temple was Mokurai, Silent Thunder. He had a little protégé named
Toyo who was only twelve years old. Toyo saw the older disciples visit the master’s
room each morning and evening to receive instruction in sanzen or personal guidence in
which they were given koans to stop mind-wandering.
Toyo wished to do sanzen also.
“Wait a while,” said Mokurai. “You are too young.”
But the child insisted, so the teacher finally consented.
In the evening little Toyo went at the proper time to the threshold of Mokurai’s sanzen
room. He struck the gong to announce his presence, bowed respectfully three times
outside the door, and went to sit before the master in respectful silence.
“You can hear the sound of two hands when they clap together,” said Mokurai. “Now
show me the sound of one hand.”
Toyo bowed and went to his room to consider this problem. From his window he could
hear the music of the geishas. “Ah, I have it!” he proclaimed.
The next evening, when his teacher asked him to illustrate the sound of one hand, Toyo
began to play the music of the geishas.
“No, no,” said Mokurai. “That will never do. That is not the sound of one hand. You’ve
not got it at all.”
Thinking that such music might interrupt, Toyo moved his abode to a quiet place. He
meditated again. “What can the sound of one hand be?” He happened to hear some water
dripping. “I have it,” imagined Toyo.
When he next appeared before his teacher, he imitated dripping water.
“What is that?” asked Mokurai. “That is the sound of dripping water, but not the sound of
one hand. Try again.”
In vain Toyo meditated to hear the sound of one hand. He heard the sighing of the wind.
But the sound was rejected.
He heard the cry of an owl. This was also refused.
The sound of one hand was not the locusts.
For more than ten times Toyo visited Mokurai with different sounds. All were wrong. For
almost a year he pondered what the sound of one hand might be.
At last Toyo entered true meditation and transcended all sounds. “I could collect no
more,” he explained later, “so I reached the soundless sound.”
Toyo had realized the sound of one hand.

2259: <p>In sanghas following the tradition of Zen Master Thich Nhat Hanh, to show appreciation one does not clap, instead one flaps his/her hands. This silent visual applause is similar to the sign for applauds in American, British, French and possibly other sign languages used by deaf persons.</p>

<p>Which other buddhist traditions also use silent visual applause to show appreciation? What is the origin of this way of showing appreciation in buddhism, was it borrowed from a sign language, and if so where and when?</p>
 254: <p><a href="https://www.youtube.com/watch?v=cVF4hmWvCe0" rel="nofollow">This video</a> says that it's widespread among French and German university students, ecologists, especially left-wing, for example at political assemblies and unions. And it says that an internet search shows that it's part of the "language of signs" but that no-one knows which country it began in.</p>

<p>The page <a href="http://www.dharmaschool.co.uk/monks-and-nuns-from-thich-nhat-hanh-collective-in-plum-village-france-pay-our-school-a-special-visit/" rel="nofollow">Monks and nuns from the Thich Nhat Hanh collective, in Plum Village, France, pay our school a special visit</a> suggest that Thich Nhat Hahn are:</p>

<ul>
<li>From France</li>
<li>Teaching 'silent applause'</li>
<li>Teaching 'ecologist' songs such as "I love nature"</li>
</ul>

<p>So perhaps they adopted the gesture from that <em>milieu</em> (or vice versa): i.e. from European students and young ecologists.</p>
 811: <p><strong>The Sound of One Hand = "quiet sound" (Soundless Sound - Emptiness)</strong> </p>

<p>At some point, completely quiet heart that does not even sound that can make us being distracted. Ears are hearing is still heard, but absolutely not disturbed mind. It is "beyond" all sound.</p>

<p>That is, in silence we "<strong>hear</strong>", "<strong>see</strong>", "<strong>understands</strong>" or "<strong>enlightenment</strong>" is many things, but when the mind is being distracted because of the "noise" we do not hear, do not see, do not understand.</p>

<p><strong>The Sound of One Hand (101 storie Zen -Nyogen Senzaki)</strong></p>

<p>The master of Kennin temple was Mokurai, Silent Thunder. He had a little protégé named
Toyo who was only twelve years old. Toyo saw the older disciples visit the master’s
room each morning and evening to receive instruction in sanzen or personal guidence in
which they were given koans to stop mind-wandering.
Toyo wished to do sanzen also.</p>

<p>“Wait a while,” said Mokurai. “You are too young.”</p>

<p>But the child insisted, so the teacher finally consented.</p>

<p>In the evening little Toyo went at the proper time to the threshold of Mokurai’s sanzen
room. He struck the gong to announce his presence, bowed respectfully three times
outside the door, and went to sit before the master in respectful silence.</p>

<p>“You can hear the sound of two hands when they clap together,” said Mokurai. “Now
show me the sound of one hand.”</p>

<p>Toyo bowed and went to his room to consider this problem. From his window he could
hear the music of the geishas. “Ah, I have it!” he proclaimed.</p>

<p>The next evening, when his teacher asked him to illustrate the sound of one hand, Toyo
began to play the music of the geishas.</p>

<p>“No, no,” said Mokurai. “That will never do. That is not the sound of one hand. You’ve
not got it at all.”</p>

<p>Thinking that such music might interrupt, Toyo moved his abode to a quiet place. He
meditated again. “What can the sound of one hand be?” He happened to hear some water
dripping. “I have it,” imagined Toyo.</p>

<p>When he next appeared before his teacher, he imitated dripping water.
“What is that?” asked Mokurai. “That is the sound of dripping water, but not the sound of
one hand. Try again.”</p>

<p>In vain Toyo meditated to hear the sound of one hand. He heard the sighing of the wind.
But the sound was rejected.</p>

<p>He heard the cry of an owl. This was also refused.</p>

<p>The sound of one hand was not the locusts.</p>

<p>For more than ten times Toyo visited Mokurai with different sounds. All were wrong. For
almost a year he pondered what the sound of one hand might be.</p>

<p>At last Toyo entered true meditation and transcended all sounds. “I could collect no
more,” he explained later, “so I reached the soundless sound.”
Toyo had realized the sound of one hand.</p>
