The following question is motivated by another question, now removed by the OP, and that I feel it didn't received enough attention.
More than a decade later, about the time that our feudalism was in the last throes of existence, Carl Marx, writing his Capital, called the attention of his readers to the peculiar advantage of studying the social and political institutions of feudalism, as then to be seen in living form only in Japan. Source
In the text above, I found very confusing the use of "to be seen" to refer to a current fact. From the context, I imagine the meaning of this phrase is:
as then seen to be in living form only in Japan
as then seen in living form only in Japan
This ngram hints that "as to be" is an expression falling in disuse.
I have tried to locate similar uses, but this has proven to be a "find a needle in a haystack" job because of other more common uses of "as to":
so as to do something "she had put her hair up so as to look older"
so good as to do something "Would you be so kind as to do this for me?
such a way as to be "Under these conditions, the communications from the more powerful person is structured in such a way as to be totally inconsistent"
For this question, I'm hoping someone can shed some light on:
- the use of "as to be"
- and perhaps some of the history behind this use.