#thatlogicproblem round-up

C: $K_A m; \\ K_B d.$

A: $\neg K_A d; \\ m \vDash \neg K_B m.$

B: $d \not\vDash K_B m; \\ (K_A(\neg K_B m)) \vDash K_B (m,d).$

A: $m \wedge K_B(m,d) \vDash K_A (m,d).$

Albert, Bernard and Cheryl have had a busy week. They’re the stars of #thatlogicproblem, a question from a Singapore maths test that was posted to Facebook by a TV presenter and quickly sent the internet deduction-crazy.

First of all: no, it’s not meant to be answered by an average Singaporean student. It’s a hard question from a schools Olympiad test.

Eight Easy Pieces (you can touch but don’t look)

Here’s a bar bet you can’t lose. Actually, it’s more of a kitchen bet, being a quiche cutting conundrum.

You’ve just bought a lovely fresh haggis quiche at your local Minus 4 shop and are planning to eat it in one sitting, in your kitchen with a friend. You’ve agreed to share it in the fairest possible way: one of you cuts and the other choses. The quiche is in the usual circular shape.


A coin is tossed—rather unnecessarily, it must be said—and it is determined that your friend gets to cut. You step out of the kitchen for a moment and upon your return discover to your horror that your friend has already done the cutting, but not as you had expected. Instead of making one simple straight cut as close to a diameter as possible, the big oaf has made four straight cuts.

Bread & Kisses

bread and kisses

Bread & Kisses is a short film by Katherine Fitzgerald about a mathematician who discovers love – I know, I know, you’ve heard this one before – but it also contains a mathematician who moves to the Alps to get more skiing in, so it’s the most realistic film about mathematicians ever. It also features the emotion of love in a star turn as an epsilon term.

Although it contains the line, “you forgot the most important ingredient: love”, so don’t get your hopes too high.