### Imre Leader

- on set theory
*Part IA, Numbers and Sets*

Quotations:

"Some *k!* nonsense..."

"There's your friend over there - you've got an r-set, how would you name it to him?"

"Pause, take a breath and say, 'Okay, is that the answer then?'"

"The way to go wrong is to do it in your head all at once."

"Every r-set is equally special."

"You could, if you wanted to, make it look more complicated."

"This is just an abhomination."

"You are allowed to be frightened of the big sigma sign."

"This is one time where we don't want an advert for induction."

"We pray it's 1..."

"I'm supposed to mention the complex numbers."

"I hope you'll ignore it."

"Just some silly definition..." ( + and . on the complex plane)

"It's not all rubbish."

"You aren't allowed cars in your set."

"For every x in the whole world..."

"B is some sort of bigger blob." (describing subsets)

"I'll first say it in a rubbish way, and then in a more careful way."

"Good old *x*^{2}."

"Everything [in B] gets hit by something [in A]."

"The infinite world is very different."

"Poor old 1 just goes to itself."

"Specify x to a friend..."

"At the beginning of all time - Chapter One."

"When some nonsense holds..."

"The big set upstairs..."

"At the end of all time, we haven't listed all the members of Z."

"Hop back and forth..."

"It's a miserable 2-case thing, isn't it?"

"At the end of all time, you'd not have counted your set."

"We have the union of this, for all k greater than 1000, as 1000 varies over the naturals."