How do you say "after all", in the sense of reaffirming or justifying a previous statement?


For example:

  * "You should wear a jacket. After all, it's snowing out there."
  * "Of course I bought you a present! It's our anniversary after all."

I tried an online dictionary but they gave me a lot of different words. けっきょく
seems like a different sort of "after all", more like "in the end." だって seems
closest to what I want, but it's listed as a colloquialism and I'd like
something more formal. There's しょせん, どうせ, やはり, and それもそのはず, and I'm not sure
which if any of them are appropriate.

I've also read だから and なぜなら used in this context being translated as "after
all", but is that accurate?




I think for this "after all", your best choice is だって.

> You should wear a jacket. After all, it's snowing out there.  
>  ジャケット着たほうがいいよ。だって、雪が降っているからね。
>
> Of course I bought you a present! It's our anniversary after all.  
>  もちろんプレゼント買ってあるよ。だって、俺たちの記念日じゃん。

If you want a formal sentence, I think you should have different example
sentences. Especially the second sentence seems to suggest an informal
situation.

In a more formal context, you might want to try

  * なんでかというと
  * なぜかというか
  * なぜなら

(increasing order of politeness) to justify a preceding statement.

I would say, though, that a more formal situation would usually imply more
careful phrasing, e.g.

> It's snowing outside, so I would suggest you wear a jacket.

And, finally, none of the other options you listed fit this use of "after
all". (For what it's worth, I checked an [English
dictionary](http://www.oxforddictionaries.com/us/definition/english/after#after__22)
and the way you use "after all" in your example sentence is not listed there.)

