Meaning of だけはわからない


> それでも彼には、自分のこと **だけはわからない** 。

I'm translating the above sentence from Japanese to English, and I'm having
issues with understanding what **だけはわからない** means.

[Why does だけ come before
は?](https://japanese.stackexchange.com/questions/45184/why-
does-%E3%81%A0%E3%81%91-come-before-%E3%81%AF) says that だけは means 'at least';
and
[https://jisho.org/search/だけは](https://jisho.org/search/%E3%81%A0%E3%81%91%E3%81%AF)
supports this with a definition of 'at least not (when followed by a
negative)'. I know that わからない means 'to not understand' as its わかる in the
negative form. When I tried to translate the above, the resulting sentence
made barely any sense (Example 1) or it failed to convey the 'abstracting
focusing' aspect of
[のこと](https://japanese.stackexchange.com/questions/2102/what-is-
the-%E3%81%93%E3%81%A8-in-sentences-such-
as-%E3%81%82%E3%81%AA%E3%81%9F%E3%81%AE%E3%81%93%E3%81%A8%E3%81%8C%E5%A5%BD%E3%81%8D%E3%81%A0/2216#2216)
(Example 2).

Example:

> 1) Even so, he understands anything but not what is only about himself.
>
> 2) Still, he at least doesn’t understand himself.

What do I need to know in order to properly understand what **だけはわからない** means
in the above sentence?




> 「～～だけ + は + Verb + ない」

is the pattern you will need to learn as it is commonly used. **It is an
expression that describes the single or very few exceptions to a phenomenon**.
It means:

> "Someone [Verb] everything but/except ~~."

Thus,

> 「それでも彼には、自分のことだけはわからない。」

means:

> "He, however, knows/understands everything but about himself."

or

> "Things about himself are the only thing he does not understand."

To give you an actual example of the most commonly-used phrases in the real
Japanese-speaking world, you will hear something like:

  * 「野菜{やさい}は大好{だいす}き。でも、ピーマンだけは食{た}べられないのよね。」 

That means "I love vegetables. I eat all kinds except for the bell pepper."

  * 「お前{まえ}だけはわからん！」 said jokingly most of the time

This means "I understand a lot of people but you!" This is said when the other
person has been acting strange.

It **_does not_** mean "Only you don't understand (something)." or "You are
the only person who doesn't understand (something)."




> 「～～だけ + は + Verb + ない」

is the pattern you will need to learn as it is commonly used. **It is an
expression that describes the single or very few exceptions to a phenomenon**.
It means:

> "Someone [Verb] everything but/except ~~."

Thus,

> 「それでも彼には、自分のことだけはわからない。」

means:

> "He, however, knows/understands everything but about himself."

or

> "Things about himself are the only thing he does not understand."

To give you an actual example of the most commonly-used phrases in the real
Japanese-speaking world, you will hear something like:

  * 「野菜{やさい}は大好{だいす}き。でも、ピーマンだけは食{た}べられないのよね。」 

That means "I love vegetables. I eat all kinds except for the bell pepper."

  * 「お前{まえ}だけはわからん！」 said jokingly most of the time

This means "I understand a lot of people but you!" This is said when the other
person has been acting strange.

It **_does not_** mean "Only you don't understand (something)." or "You are
the only person who doesn't understand (something)."

