# Particle と with へ; ～へと

Consider ～へと in these cases:

• ～へと下がる : (of some quantity) to fall to ~
• ～へと先送りされる : to be postponed to ~
• ～へと旅立つ : to make a trip to ~
• ～へと広がる : to spread to ~

へと seems to be equivalent to へ or even に.
How is へと different from へ?
How is へと different from に?
What does と do and what nuance does it add?

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I understand it, but I sure can't explain it. –  istrasci Nov 7 '12 at 15:30
[Copied from my chat in case you have not seen it]:I dicussed this with my teacher last year. I did not get to the bottom of it to my satisfaction but he was quite clear that it was the same と　as used in quotations. He gave the example of a road fork with the sign showing one road was going to Tokyo and the other Osaka. My note says that in this case (according to the sigh)「東京へ」とつづく. This is what you have in your examples. I think the more precise word this とis "an adverbial predicate" or something - need to check Makino's Dictionary of Basic Japanese Grammar. –  Tim Nov 7 '12 at 21:48

へと is used when you are directing your audience's attention to the content that comes after the と for emphasis. 「やや強意の副詞的表現に属することを表す」
Example:

The white ball disappeared into the crystal clear blue sky

Without the と it is simply a statement of fact.
Q: "What did the ball disappear into?"
A: "The blue sky."
The end.
But with the と, the "crystal clear blue sky" is emphasized in the mind of your audience.

Of course this means that the same sentence without the と would be grammatically correct, be understood by native speakers, and most likely not be thought of as unnatural or needing correction of any sort. The difference is in the imagery you paint in the mind of your audience along with the associated feelings.

Of the examples in the question I think this is easiest to see with

～へと先送りされる : to be postponed to ~

If we say
7月15日へ先送りされる。 Then something has been postponed until July 15. A simple statement of fact. But if we say
7月15日へと先送りされる。Then something has been postponed until July 15 and we are letting our audience know that we feel this is far away and is going to be a long wait.

Which leads to another usage of へと. By breaking the flow of the sentence with と, you indicate that the content that comes next did not happen easily or without effort. 「へ」より「へと」のほうが「長い道のりを経て」 This is probably easiest to see with

～へと旅立つ : to make a trip to ~

If we say 北海道へ旅立つ。 Then all we are saying is that we made a trip to Hokkaido.
But if we say

Conclusion
へと seems to be equivalent to へ or even に.
It is, in terms of meaning, but as you can see above the feeling can be quite different.
How is へと different from へ?
The difference is in the emphasis that と brings to the sentence.
How is へと different from に?
There are many cases where へ and に are the same. The 広辞苑 dictionary uses に in definition 2 of the particle へ. So since the と is adding emphasis, the answer to this question lies in the difference between へ and に, which is beyond the scope of this Q&A. On a side note though, に and と also have such a relationship. (～となる and ～になる)
What does と do and what nuance does it add?
I hope the above answer has made that clear by now. (^_^)

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I expect to see/hear「税率が10パーセントへと下がる」on newspaper or TV news. I'd say「税率が10パーセントに下がる」in normal conversation. (I'm not sure if we say「税率が10パーセントへ下がる」.)

「来年度へと先送りする」「来年度へ先送りする」are what I expect to see/hear on newspaper or TV news. I think I use「来年度に先送りする」in daily conversation, and I wouldn't say 「来年度へと先送りされる」when I talk casually.

To me,「旅客機は東京へと旅立った」sounds more literary than「旅客機は東京へ旅立った」, and「旅客機は東京へ旅立った」sounds more literary than「旅客機は東京に旅立った」.「~~へと旅立った」sounds a bit elegant and poetic too. I think we normally say 「旅客機は東京に"出発し"た」when we talk casually.

Among「～～へと広がっている」「～～へ広がっている」「～～に広がっている」, the first sounds most literary and the last sounds most colloquial to me, but「～～に広がっている」can also mean "(something) has spread throughout~~" "(something can be seen) all over~~" while 「～～へと広がっている」「～～へ広がっている」sound more like "Something is spreading TO~~". (For example, you might see the difference between 「大空に広がる雲」 and 「大空へと広がる雲」.)

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