Efficiency is highly overrated； Goofing off is highly underrated. Regularly scheduled sabbaths， sabbaticals， vacations， breaks， aimless walks and time off are essential for top performance of any kind. The best work ethic requires a good rest ethic.
The medium is the metaphor.
光波，无论是以太波还是其他波，在所有情况下都是时间上的周期性过程。
"The only way to get rid of a temptation is to yield to it."