There was significant revision in astronomy recently. Important decision is for Pluto to have deviated from a planet. An argument whether we put a new star in a planet seems to have affected it. When conventional knowledge is established anew, there is sense of incongruity.

　It happened the other day that my knowledge was established anew.
When there are 40 classes, the establishment that nobody is already a person of the same birthday in that seems to be considerably high.
　It is some mysterious feeling.