Es más listo que el hambre

Es más listo que el hambre
 

In English?

He is razor sharp.

When was the word "razor" first used in the English language? ;)

"Razor" is from Middle English "rasour" from Anglo-French "rasur", and apparently came into use
in English sometime after the Norman invasion of England in 1066. Merriam Webster gives 14th century.

In addition to Perikles' excellent suggestion, you can also say "to be as smart as they come."

I couldn't get the date in Merriam, just Middle English.

Yes, for us rasurar(afeitar) = shave

Thanks.

Presumably, that came from Latin rasus, past participle of radere: to scrape, shave, with associated words arrasar, arrastrar, rallar, ras, rascacielos, rascar, rasurar, etc.

Under Onelook Dictionary Search, Merriam Webster's Online Dictionary,
11th edition, says 14th century. That Onelook site is great...

Thanks for the link - it looks extremely useful. The reverse dictionary function could be useful as well. You type in your definition, and it comes up with suggestions for the word. Sometimes. :)

Correct, I imagine. :)

I would imagine also, that rasurar is closer to "ras" thence "rasar".

For the original "ser más listo que el hambre", Cabridge/Klett bilingual also gives "to be no fool", and Random House gives, 6. be nobody's fool, to be wise or shrewd.
In Spanish "ser más listo que Cardona" "no chuparse el dedo" "cortar un pelo en el aire" "no tener un pelo de tonto" "sabérselas todas" "no ser zurdo" or "ser un lince", "saber más que Lepe [,Lepijo y su hijo]" are all expressions to convey that one is intelligent, clever, smart, shrewd, with different connotations each. I think the best translation back to English for "cortar un pelo en el aire" is "to be razor sharp", (i.e., if you are able to slash/cut a hair on the air, you must be really sharp.)
On "ser más listo que el hambre" I believe the expression comes from the idea of the fact that "hunger" (or “necessity level”) makes one think sharper, as one has to figure out how to survive. Literally the Spanish expression is "to be smarter than hunger", making “hunger” into an entity, i.e, ‘personifying’ ‘Hunger’, attributing human nature or character to it.
There are some additional English expressions that may be adequate in some contexts, “To be as sharp as a tack", “be as sharp as a needle” “to be bright as a button”. (In fact, while the translation “to be razor sharp” would be the best in the majority of the cases, the one of “being sharp as a needle” may convey a bit more the “flavour” of “being” hungry, and somewhat, the Spanish way of saying it has a similarity with the quote, Necessity makes even the timid brave. (In the case of the Spanish, “Necessity makes the dull bright” or “the average guy very intelligent”)
In checking in Google, you have, Necessitas Magistra. "Necessity is the mother of invention, and the most powerful provoker of industry, and ingenuity." La necessite n'a point de loi," and "La necessidad carece de ley." "Necessity has no law," and "Hunger will break through stone walls." "In genii largitor venter, Csutum e rudi reddit magistra necessitas." Necessity makes the dull man bright, the sluggard active, the unwary cautious. It sharpens the wit, and makes men more apt for instruction. (I copied the Latin as I found it, with the English translation.) (And now I am going to eat something, so I stop being such a smart-...) (I omit the word with the double ss and the a.) At any rate, I hope it helps. (It helped me to get some tips to increase my IQ, or reduce it at will!)