If you said "hi" and I responded "share the day" how would you react?
"Share the day" is a greeting phrase uttered by the Sharer race in Joan Slonczewski's "Door Into Ocean." It reflects their philosophy of all things as shared; if you hit the nail with the hammer, the nail also hits you as you feel the reflected force through the hammer into your hand. In the sharer language you would not "hit the nail" you would "share force" with the nail. All things are mutual. So "share the day" is a short way of saying "we share awareness of our impact on each other because we are both alive today and all things are interconnected."