How much time do you need to finish this?
How much attention do you need to finish this?
How much sleep do you need to feel fresh?
How much rest do you need to feel fresh?
Just like how time is so different from attention, I feel rest and sleep have a related, important distinction, too.
Time, like sleep, suggests quantity. Attention, and rest suggests quality.
And if you think about it, we go through life swapping time to get sleep, sleep to get rest, and rest to gain attention to do what we do best, before we head back to sleep again.
There may be some math behind the semantics, but I just woke up from an 8 hour slumber, and screw the math, I think I could use a bit more
sleep rest ;p