Silence.
The sound of cicadas is so loud that they seep into rocks (haiku by Basho)
It is because the summer of the cicada swarms has gone.
The quietness is felt by remembering.
This summer, the trees of the northeastern United States were covered with 17-year cycle cicadas.
Hundreds of billions of them, more than you can imagine!
No, perhaps we just forget to imagine.
The mind is an activity, not a repository.