"I have to admit that he was not bad at combinatorial analysis - a branch, however, that even then I considered to be dried up."

Next Quote

But many, many stories were told; from what could be gathered, all fifty of the mine's inhabitants had reacted on each other, two by two, as in combinatorial analysis, that is to say, everyone with all the others, and especially every man with all the women, old maids or married, and every woman with all the men. All I had to do was to select two names at random, better if different sex, and ask a third person, "What happened with those two?" and lo and behold, a splendid story was unfolded for me, since everyone knew the story of everyone else.

— Primo Levi