If my grandmother had wheels, she would be a wagon.
Old saying, with many variants.
If all the world were paper
And all the sea were ink
And all the trees were bread and cheese
What would we have to drink?
Anonymous. There is a version here with seven verses.
I think, if I were King of Greece
I'd push things off the mantlepiece.
A.A. Milne,
If I Were King
One Jew saw another eating on Tzom Gedaliah [a minor fast day]
and asked why he wasn't fasting.
He answered, "In the first place, if Gedaliah had not been killed,
would he still be alive? And in the second place,
if I had been killed, would Gedaliah fast for me?
And in the third place, I don't fast on Yom Kippur, so why would I fast
on Tzom Gedaliah?"
--- Anonymous
In response to Heidegger's ontological query "Why is there something rather
than nothing?" Morgenbesser answered "If there were nothing you'd
still be complaining!"
--- Sidney Morgenbesser
Were you not to Ko-Ko plighted
I would say in tender tone
"Loved one, let us be united .
Let us be each other's own!"
I would merge all rank and station
Worldly sneers are nought to us
And, to mark my admiration
I would kiss you fondly thus.
W.S. Gilbert, The Mikado.