A lisp riddle has been printed on many images (often with a photo of boxer Mike Tyson) :
   
Q: How do you think the unthinkable?
A: With an itheberg.
 
The “How do you sink the unsinkable? With an iceberg” is a joke on the RMS Titanic, a ship that hit an iceberg and sank on April 15, 1012. The joke was first posted on Twitter on August 31, 2014.
 
   
Wikipedia: RMS Titanic
RMS Titanic (/taɪˈtænɪk/) was a British passenger liner that sank in the North Atlantic Ocean in the early morning hours of 15 April 1912, after it collided with an iceberg during its maiden voyage from Southampton to New York City. There were an estimated 2,224 passengers and crew aboard the ship, and more than 1,500 died, making it one of the deadliest commercial peacetime maritime disasters in modern history. The RMS Titanic was the largest ship afloat at the time it entered service and was the second of three Olympic-class ocean liners operated by the White Star Line.
     
Twitter     
Enzo Arias
@Eeeightytwo
How do you think the unthinkable? With an itheberg.
2:12 AM - 31 Aug 2014
 
Twitter
Kevin
@KevinAMLewis
How do you think the unthinkable? With an itheberg.
4:13 AM - 31 Aug 2014
 
Twitter
Stavros Korokithakis
@Stavros
Q: How do you think the unthinkable?
A: With an itheberg.
4:37 AM - 31 Aug 2014
 
Reddit—Jokes
How do you think the unthinkable?
submitted September 7, 2014 by albinekman
With an itheberg.
 
Reddit—Jokes
How do you think the unthinkable?
submitted September 22, 2014 by Swingtortoise
With an itheberg
 
Reddit—Jokes
How do you think the unthinkable?
submitted October 17, 2014 by MrDurka
With an Ithberg
 
Reddit—Dad Jokes
What thinks the unthinkable? (self.dadjokes)
submitted November 1, 2014 by AgeTurnipseed
An ithberg.
 
Reddit—Jokes
How do you think the unthinkable?
submitted November 13, 2014 by Kinakuta
With an ithberg!
   
Reddit—3amjokes
What can think the unthinkable? self.3amjokes
Submitted March 27, 2015 by andycooktellemWOOOOO WHEEEE
An itheberg.
   
Jokes Explained
How do you think the unthinkable?
February 10, 2017
How do you think the unthinkable? Ithburgth.
 
This joke is really horrible. For this joke to be funny, the listener has to first realize that the jokester is attempting to mimic a lisp (a speech impediment where they can’t say an ‘s’ sound), and then they have to remember that the Titanic (the ship, not the movie), was supposed to be unsinkable, but it was sunk by an iceberg.
 
Reddit—Dad Jokes
How do you think the unthinkable (self.dadjokes)
submitted March 31, 2018 by ChanandlerBong4
With an ithberg