What would you call a person who doesn't want to learn new things and even maybe thinks that this is unnecessary since he knows enough already? An ignorant person?
a person who doesn't want to learn new things (and even maybe thinks that this is unnecessary since he knows enough already)
If you consider Mitch's close-minded a good answer then there are similar idioms that are possibly applicable, for example:
None of these are specific to learning so you should use them in a clear context.
Now let me focus on a different perspective - desire to learn new things often stems from curiosity, so here is a list of some antonyms of curiosity
Again none of these terms is specific only to a person who does not want to learn new things, but they all might be applicable and true of such a person.
Maybe if you combine some of the first sort and the second you might arrive to interesting expression applicable to your case; or you might want to think about why the person you are trying to describe does not want to learn new things and a better phrase or a word might present itself.
EDIT: Also, there is a third perspective, someone who is not studious is unstudious (synonyms: unscholary); both of which are not very common, but might just be a right word for your case.
Keep in mind that they do not imply "that they might even think it is unnecessary since they know enough already".
One term I sometimes use is: Willfully ignorant (adjective). Willful ignorance (noun). Other variants are wilfully and wilful (although they are not found in my computer's dictionary, they can be found on Google).
That may or may not apply to your particular case, depending on what exactly you are after. For example, if it is clear that the person has ready available access to sources to learn something new, knows about it, but still just doesn't do it, and thus remains ignorant, I believe this term can be used.
I always call them Luddites if they're opposed to new technology and the knowledge needed to make use of it.
As well as the various good examples above, you could describe such a person as a "stick in the mud" (sometimes hypenated as "stick-in-the-mud"). This isn't an exact fit, but the basic meaning of "someone who is not open to change" has a strong connection to being unwilling to learn too.
(Aside: I find the first Wiktionary definition I linked to odd and unconvincing. You could infer that a stick-in-the-mud would be a party pooper, but it's not a synonym.)
I'll submit: "Stubborn", for the implication of being settled on ones opinion / knowledge, and unresponsive / unwilling to extend or change it.
Possibly an old dog, as in the idiom, You can't teach an old dog new tricks:
something that you say which means it is difficult to make someone change the way they do something when they have been doing it the same way for a long time: You're never going to teach your father at the age of 79 to use a computer. You can't teach an old dog new tricks, you know.
A smug, ignorant, especially middle-class person who is regarded as being indifferent or antagonistic to artistic and cultural values.
A matter-of-fact, commonplace person; a man upon whom one can look down, as of culture inferior to one's own; one of “parochial” intellect; a satisfied person who is unaware of his own lack of culture.
Of or pertaining to or having the characteristics of Philistines in the modern social and literary sense; commonplace; dully matter-of-fact and satisfied; conventional and unimaginative.
Negligent (in studying, learning new things)
The person neglects the fact that he needs to learn new things.
Note that I have a very specific scenario in mind. I'm not sure if it applies to what the OP has in mind. This scenario is the following:
He works in the IT area and knows some technologies (e.g. programming languages) and uses them at work. He doesn't think that that he needs to know any of the new technologies that are coming out. However, in IT things change quite fast and his knowledge may soon be out-of-date due to the new technologies. He neglects that with the assumption that he simply doesn't need to learn anything new as if what he already knew was everything he needed to know for the rest of his career.
In the Comfort Zone
Example from Merriam-Webster:
I need to expand my comfort zone and try new things.
How about "unteachable"?
It's got some biblical connotations, i.e., "an unteachable spirit".
"Teachable": Capable of being taught; apt to learn; also, willing to receive instruction; docile. (http://machaut.uchicago.edu/?resource=Webster%27s&word=teachable&use1913=on)
An unwillingness to learn would be considered unteachable, I suppose.
(P.S. - I didn't want to post the hyperlink directly; I'm new here, so I'm not sure what etiquette applies. Googling the term obviously brings up a whole lot of answers.)
To help me focus and stay true to OP's question.
Someone who believes they know enough of everything there is to know. Someone who doesn't want to learn new things is also a person who doesn't listen and refuses to admit their knowledge could be expanded upon.
An ignorant person?
As I live in Italy there's is only one person I can think of who fits that description to a "t".
I am not being facetious. In Italy we have the expression: Berlusconiano and it is used to describe pretty much someone who believes they are irreprehensible. (You could translate it to "Berlusconian").
Failing that, the word arrogant I believe fits the criteria requested.
having or showing an exaggerated opinion of one's own importance, merit, ability, etc.; conceited; overbearingly proud; an arrogant teacher; an arrogant assumption.
I don't want to make this a political discussion, though I do think my answer proves a worthy interrogation of the political terms I allude to.
A 'conservative' is exactly a person who is philosophically averse to the new. Convservative cultures prefer existing norms over those newer behaviours that arise through the inherent change that exists in the world. Conversative politics infers an aversion to new ways of conducting business . . . the tried and true over the innovative. I think it's the perfect term that the poster is looking for.
"Yahoo," as invented by Swift.
The Redneck Manifesto: How Hillbillies Hicks and White ... - Page 82 Jim Goad - 1998
in the despicable Yahoos, "who appear to be the most unteachable of all animals." Swift,
I think you are asking for a kind of person that is not interested in external ideas or even in their own ideas—people that are not interested in anything or anyone, not even in themselves, and only live as they can. I could call those kind of people "suicide", cause the tools of humans are the knowledges and the information. If we don't have some knowledge, we are putting our existence at risk.