Who is performing the actions in this sentence?


I have a question about the last sentence here taken from
[this](http://eow.alc.co.jp/%E3%81%9D%E3%81%AE%E5%B9%BB%E6%83%B3%E7%9A%84/UTF-8/?ref=ex&exp=HT118103&dn=2268026&dk=JE&pg=1)
essay:

> やっぱり旅っていいな…としみじみ感じます。  
>  'Then you will know the true joy of travelling.'
>
> 食事の後はちょっと外へ出てみましょう。  
>  'After your meal, go outside for a while.'
>
> なんと宿のすぐ裏でホタルたちが一面に乱舞。  
>  'You will see a myriad of fireflies dancing right behind the inn.'
>
> その幻想的なことといったら息をのんでしまうほどです。  
>  'The phenomenon will take your breath away.'

The English translation provided, though conveying the right idea, is very
loose. Here is my more literal translation (which doesn't flow as nicely):

> 'Just speaking of such a fantastic thing, it's enough to take one's breath
> away.'

I am wondering who is speaking in this sentence and whose "breath is being
taken away" (yes my translation is still quite figurative). Is it (a) the
speaker (I guess this is called 1st person singular)? = "Just speaking of such
a fantastic thing takes my breath away" Or is it that (b) if "one were to
describe the event it would take one's breath away" = (third person singular)?
Or (c) a combination of these = 'If I spoke of these things it would be enough
to take your breath away" or (d) just ambiguous? If there is a clear answer,
how can one ascertain who is performing these actions?

Edit: Or perhaps I should understand these as two figurative phrases?
その幻想的なことといったら = such an amazing thing 息をのんでしまうほどです。=just breath-taking!

I apologize in advance for my ignorance of grammatical terms.




I'm not exactly sure where in the sentence you face the problem, but I'm going
to guess that it's with:

  1. Implicit agency

  2. Implicit experiencer

  3. The ~といったら sentence pattern

* * *

First let's fix 1. and 2.

You must have realised by now that the Japanese language is so to speak
"sparse" because quite often you will encounter sentences that are seemingly
ambiguous because no specific persons are mentioned.

> [Person A] どこ行くの？
>
> [Person B] (私は)図書館に行く。

The context makes who is performing which action evident. Without context,
(i.e. you just walked in on a conversation and only heard `図書館に行く`) it could
be anybody who is going to the library.

Now notice that you have one contextual clue in your second sentence - `ましょう`.
Usually this is used in a cohortative sense of "let us do ~" or "shall we do
~?". The subsequent sentences can either involve the speaker, the listener or
both. The context given is that the speaker is inviting the listener to go
outside to enjoy the fireflies.

Consider which of the sentences are appropriate:

> Existing contextual information: Intention is to share the firefly-
> phenomenon
>
> Invitational Sentence:
>

>> Shall we go outside after eating?

>
> Elaboration 1:
>

>> A. **I** will see a myriad of fireflies dancing right behind the inn

>>

>> B. **You** will see a myriad of fireflies dancing right behind the inn

>>

>> C. **We** will see a myriad of fireflies dancing right behind the inn

>
> Elaboration 2:
>

>> A. The phenomenon will take **my** breath away

>>

>> B. The phenomenon will take **your** breath away

>>

>> C. The phenomenon will take **our** breath away

Obviously choice A would feel completely unnatural. You intend to share
something with someone and end up talking only about yourself (how selfish).

Now B and C are possible ways to parse it into English for both Elaboration 1
and 2. But I feel it should sound most natural as:  

> " **We** will see a myriad of fireflies dancing right behind the inn. The
> phenomenon will take **your** breath away."

Because in the first part, the focus is on a "shared activity", namely
watching the fireflies together. And in the second part, the focus is on
"getting the other person to experience the phenomenon"; the focus is on the
other person.

* * *

Now for the ~といったら sentence pattern. Its function is similar to ~といえば, ~って,
~ったら. What it does is that it presents ~ as a topic from something that was
from a previous discourse. It is similar to the topic marker は, except that it
carries more emotive overtones.

> なんと宿のすぐ裏でホタルたちが一面に乱舞。
>
> その幻想的なことといったら息をのんでしまうほどです。 Literally: "Speaking of that phenomenon, it is
> something to the extent of taking your breath away."

