I read this expression for the first time earlier today in another thread. The poster (whose name I can’t remember and the thread is gone, so I can’t find it) said Isaac Newton and Robert Hooke were like “cheese and chalk”, meaning they did not get along well at all. Then, just a little while later, I heard the expression on the radio. I think the announcer was from the BBC, so this may be a British term. I can figure out the meaning – like “oil and water” – but here’s my question: why “cheese and chalk”? What’s the relationship between these two things that would put them in contrast to each other?
Hello!
(I think the thread is lost forever - I just emailed manhattan and Chronos about it)
Well, “like chalk and cheese” is a British idiom. It means “totally different from each other” As far as I know it’s just because cheese is greasy and yellow while chalk is dry, crumbly and white.
I shall endeavour to find out the full story behind “chalk and cheese.”
Hang on a mo…
So that’s your name. I knew it had a “T” and “n” and “u” in it, but I couldn’t put it all together. 
Maybe there are (very fine) shades of difference between these phrases. “Oil and water” refers to things that don’t mix. This phrase makes sense to me because I’ve actually seen it (in cooking and oil spills). If “chalk and cheese” means “totally different from each other”, that’s a slightly different meaning than “oil and water”. I also thought of “fire and ice”, but that means incompatible (and perhaps mutually destructive). Three similar phrase but with slightly different connotations.
Of course, that still doesn’t explain the origins of “chalk and cheese”. (Is it always “chalk and cheese” or sometimes “cheese and chalk”?) The alliteration certainly helps explain why it’s still used.
I await your research.
I agree with JeffB that the alliteration carries the phrase.
Like not knowing the difference between “shit and Shinola”.
Darn, I thought this would be about the “cloning” episode from the first season of South Park, where the mad scientist managed to cross not only mosquitos with gorillas and bunnies with fish, but also “Swiss cheese, with chalk, and a beard.”
Carry on.
It’s always “chalk and cheese.” There’s no intrinsic sense of not mixing like there is with “oil and water” — it just means that they’re completely different. It’s used of siblings when they’re wildly different from each other, with little family resemblance.
Brewer’s Dictionary of Phrase and Fable on The difference between chalk and cheese
[The Jerk]Son, you’re gonna be alright.[/The Jerk]
The difference between chalk and cheese
The cite to Brewer’s [BTW thanks for that bibliophage, saves me fossicking through my hard copy :)] makes the important distinction that the phrase relates to things that have some superficial similarity yet are totally different in character.
Look at some of the excellent English aged cheddar cheeses e.g. Cheshire which is chalk white. I hazard a WAG that the original derivation might date back to a time when an unscrupulous traders might have substituted one for the other.
IIRC, the phrases “Buying a pig in a poke” and “letting the cat out of the bag” relate to a smilar agricultural con trick i.e. a cat for a suckling pig.
East is East and West is West and 'nere the twain shall meet
or, less obscurely, Cheshire cheese is definitely not Cheddar. Made in different areas, made by different methods, different tastes and textures - in fact as different as …
I’m allowed to be picky today - I just turned 35 