Looool this is soooo stupid but I had to laugh sooo hard ahahahah 
A man gets on a bus, and ends up sitting next to a very attractive nun. Enamored with her, he asks if he can have sex with her. Naturally, she says no, and gets off the bus. The man goes to the bus driver and asks him if he knows of a way for him to have sex with the nun.
“Well,” says the bus driver, “every night at 8 o’clock, she goes to the cemetery to pray. If you dress up as God, I’m sure you could convince her to have sex with you”…
The man decides to try it, and dresses up in his best God costume. At eight, he sees the nun and appears before her.
“Oh, God!” she exclaims. “Take me with you!” The man tells the nun that she must first have sex with him to prove her loyalty. The nun says yes, but tells him she prefers anal sex. Before you know it, they’re getting down to it, having nasty, grunty, loud sex. After it’s over, the man pulls off his God disguise.
“Ha, ha! I’m the man from the bus!”
“Ha, ha!” says the nun, removing her costume. “I’m the bus driver”…
A horse walks into a bar…
and orders a ■■■■.
As the bartender serves him, he looks at the horse and says “hey, you look a little long in the face. Do you think you might be depressed?”
The horse ponders for a second, scratches his chin, and says “I don’t think I am” - and promptly disappears.
See, this is a joke about Rene Descartes’ famous statement, “I think, therefore I am.” I could have mentioned this at the start of the joke, but that would be putting Descartes before the horse.
Actually that one is quite clever.
Do I have to know Descartes or any special English to understand that?
That joke I know. Everything after I do not get 
To make it easier, the saying is " I think so i do exist", and the horse says “i don’t think”
French philosopher Rene Des__tes is famous for the quote “Cogito, ergo sum”, Latin for “I think, therefore I am.” Hence “I don’t think I am” in the joke. The phrase “To put Descartes before the horse” is a pun on the English saying “To put the cart before the horse”, which means to do things in the wrong order. It’s one of those clever clever jokes. The answer to both your questions is yes. I’m not English speaking either, but I knew the joke. It is heavy on puns.
Well you must excuse these germans regarding humour sometimes 
Very well explained for our german friends pal 
This one line is the joke. All the rest is just setup, i.e. setting you up for the punchline, that one line.
Thanks for the explanation buddy 
Don’t confuse Jabs for fucks sake
The Madam opened the Brothel Door to see a frail, elderly gentleman.
“Can I help you”…?? the Madam asked.
“I want Natalie,” the Old Man replied.
“Sir, Natalie is one of our most Expensive Ladies, perhaps someone else”…???
“NO, I must see Natalie.” the old guy exclaims.
Just then Natalie appeared and announced to the Old Man, that she Charges $1,000 per visit.
Without blinking, the Old Man reached into his Pocket and handed her Ten $100 Bills.
The two went up to a room for an hour, whereupon the man calmly left.
The next night he appeared again demanding to see Natalie…???
Natalie explained that no one had ever come back Two Nights in a Row and that there were NO Discounts. It was still $1,000 a visit.
Again the Old Man took out the Money, the Two went up to the room and an hour later, he left.
When he showed up the THIRD Consecutive night, no one could believe it.
Again he handed Natalie the money and up to the room they went.
At the end of the hour Natalie questioned the Old Man:- “No one has ever used my Services Three Nights in a Row. Where are you from Sir”…???
The Old Man replied, “I’m from Philadelphia.”
“Really”…?? replied Natalie.
“I have Family who Lives there.” she replies.
“Yes, I Know,” said the old man.
“Your F____r Died recently, and I’m your Sister’s Attorney”.
*“And she asked me to give you this $3,000, when I saw you”…
