If you went back in time
To kill Hitler as a baby
You probably should consider
That someone else just maybe
Might go back in time again
This time to kill you
‘Cause you’re a time-traveling baby killer
As far as they knew.
That’s why if you ever
Change history somehow
By traveling to the past
To influence the now
I think it’s important
To leave a detailed letter
Explaining how killing babies
Can make the world better.