Example:
I'm a mule when it comes to math.
Is this usage common? If not, what other animal or object is more widely used by native English speakers?
Example:
I'm a mule when it comes to math.
Is this usage common? If not, what other animal or object is more widely used by native English speakers?
The idiom usually associated with mules is stubborness
stubborn as a mule
Extremely obstinate, as in He's stubborn as a mule about wearing a suit and tie. This simile evokes the proverbial stubbornness of mules, whose use as draft animals was once so common that the reputation for obstinacy can hardly be as warranted as the term indicates. [Early 1800s]
Funnily enough, donkeys are considered to be stupid animals. Think of Pinocchio and his donkey ears (and tail) that appeared when he played truant (AmEng played hooky) from school.
If the OP wishes to express someone's ignorance of math, I would suggest using a different expression.
I'm a complete idiot when it comes to math.
Alternatively, the noun numbskull is also very appropriate.
a stupid person; dolt; blockhead
I'm a numbskull when it comes to math.
Source: Tne Free Dictionary
Suggest birdbrain (informal noun):
a silly or stupid person
[Source: ODO]
a human who gives the impression of possessing a bird-size brain; a fool
[Source: The Routledge Dictionary for Modern American Slang and Unconventional English, 2009]
Example sentence:
'I'm such a birdbrain when it comes to math(s).'
A comprehensive list of synonyms for birdbrain is available through the online M-W Thesaurus
Mule, Donkey, and Ass (animal) are all used to denote stubbornness, lack of intelligence, or lack of empathy for others.
"That person is a donkey." Insult to that person's intelligence. Could also be used when a person is being socially clumsy. If you witness a person being very loud at a restaurant, calling them a donkey to your friend would be appropriate.
"What an ass" Insult to a person's sensitivity to another. If a driver cuts you off in traffic, that person is an ass. This one is a bit conflated with asshole - be careful with its use. Not everyone will hear Mule when you say Ass. Many in the US will assume you are talking about the anus.
"Don't be such a mule" Insult to a persons unwillingness to change (stubbornness) or intellect. Often a part of a longer description: "that person is as stubborn as a mule".
In Asimov's Foundation series of books, a character named Mule has the notion of strength associated to his name, as in some sort of brute force, but never the notion of lack of intelligence.
If you really want to use an animal in your specific phrase, you could try something like:
I'm like a fish out of water when it comes to math.
Or some other expression, but this is not directly related to your question title.
I can't think of a standard animal/object/phrase that would naturally fit the gap in I'm a ___ when it comes to math except for something dull like I'm a dunce when it comes to math.
If you're looking for something a bit more poetic, in British English, you can combine the informal colloquialism thick (meaning stupid) with a standard simile for emphasis and comic impact, e.g. as thick as two short planks or as thick as mince (the latter is perhaps specific to Scotland).
So if you wanted a nice idiomatic, albeit very informal, British English way to express your innumeracy you could say:
I'm as thick as two short planks when it comes to maths.
(Of course in British English we say maths rather than math.)
Others have well addressed the mule question.
As to animal terms used to convey stupidity, consider dodo
- (Informal) A stupid person; an idiot.
American Heritage Dictionary
These days mule is used more often to mean a courier who carries and delivers something illegal like drugs across borders and past checkpoints. Even though other connotations for mule still stand, using the word for anything other than illegal courier invites confusion and a bump in your reader's experience, which should be as smooth as possible.
Mari-Lou A makes a good point that a mule is considered more stubborn than stupid.
Many others have suggested other animals for stupidity, but you also might want to keep in mind that most of these are hackneyed clichés. You'd do well to forge your own expression for stupidity.
Finally please note that while dumb has through misuse come to mean stupid, it originally means a person who does not speak and who is therefore considered stupid. Since dumb evokes this bit of wrong and insensitive thinking, it too is best avoided.
In Canada, we used to say "bobo". For instance, "Don't be such a bobo!" or I suppose, "I'm a bobo at math."
I don't know why... ;)
Why restrict yourself to animals?
You could say something like, "when it comes to math, I'm just one of the Pid Brothers, but I'm not sure which one: Mo, Ron or Stu."
Or, if you prefer brevity, how about, "I'm a mathoron."
There's always, "I'm no Albert Einstein when it comes to math."
Be inventive, and that will distract from your math liabilities.
Answer
No, we don't use 'mule' with that meaning. However the term 'jackass' is commonly used especially in the USA.
Explanation
If you look for mule in an English dictionary you will see that it can mean a stubborn person or someone who carries drugs. It does not specifically signify stupidity in English.
mule noun \ˈmyül\ Definition of MULE
1 a : a hybrid between a horse and a donkey; especially : the offspring of a male donkey and a mare b : a self-sterile plant whether hybrid or not c : a usually sterile hybrid 2 : a very stubborn person
: a machine for simultaneously drawing and twisting fiber into yarn or thread and winding it into cops 4 slang : a person who smuggles or delivers illicit substances (as drugs)
In British English, calling someone an 'ass' is distinct from 'arse'. The British meaning of 'ass' refers to the animal and is another word for a donkey. It means a stupid person. However it is little used these days because of the conflict in meaning with American English where 'ass' means 'backside'.
The difference is explained in more detail here. Cambridge Dictionary
Another term - also outdated - is donkey.
I the USA they currently use the term 'jackass' to mean a foolish person. Merriam Webster
I am not aware of a current British word for fool that uses the name of an animal. However we do understand the US term jackass.