Imagine: it's year 20030 and for the N-th time, You just left Your cryogenic chamber, fresh and ready to act.
On the table, there is a bunch of letters You wrote to Your future selves with an intention to be read (and re-read) thousands and thousands of years in future.
You open the letter in the envelope with id "0" and read ...
The 0th exercise for You is to write that letter. NOW