What if this were true? I would actually argue that it is true - and that not thinking about it this way is what gets us into all sorts of short term and long term problems.
First of all - as the Dali Lama says - the ONLY days that don't matter are Yesterday and Tomorrow - because as you can quickly surmise - Yesterday is the past - nothing we can do about it - and Tomorrow is the future and we are NOT GUARANTEED we are going to see it!
So Today is crucial (its also a Privilege but that is another post) - it's critical and if it were True- how would we act? What would we do? I certainly wouldn't waste it - I'd make sure I told the people I loved that I loved them, I wouldn't be rude or short tempered - I wouldn't get angry at all - how could I do any of those things on The MOST IMPORTANT DAY of MY LIFE?
I started writing this phrase down over a year ago in my journal and had a street vendor in Siricusa make me this as a reminder that there is only one - and its not coming back