A mathematician and an engineer attend a lecture by a Physicist. The topic concerns Kulza-Klein theories involving physical processes that occur in spaces with dimensions of 11, 12 and even higher. The mathematician is sitting, clearly enjoying the lecture, while the engineer is frowning and looking generally confused and puzzled. By the end the engineer has a terrible headache. At the end, the mathematician comments about the wonderful lecture. The engineer says “How do you understand this stuff?”

“I just visualize the process,” replies the mathematician.

“How can you possibly visualize something that occurs in 11-dimensional space?” asks the engineer.

The mathematician shrugs his shoulders. “Easy, first visualize it in *n*-dimensional space, then let *n* go to 11.”