Italian; io sono stato = I am been.
German; ich bin gewesen = ditto.
which is logical.
[§ 493]. I am to speak.—Three facts explain this idiom.
1. The idea of direction towards an object conveyed by the dative case, and by combinations equivalent to it.
2. The extent to which the ideas of necessity, obligation, or intention are connected with the idea of something that has to be done, or something towards which some action has a tendency.
3. The fact that expressions like the one in question historically represent an original dative case, or its equivalent; since to speak grows out of the Anglo-Saxon form to sprecanne, which, although called a gerund, is really a dative case of the infinitive mood.
When Johnson thought that, in the phrase he is to blame, the word blame was a noun, if he meant a noun in the way that culpa is a noun, his view was wrong. But if he meant a noun in the way that culpare, ad culpandum, are nouns, it was right.
[§ 494]. I am to blame.—This idiom is one degree more complex than the previous one; since I am to blame = I am to be blamed. As early, however, as the Anglo-Saxon period the gerunds were liable to be used in a passive sense: he is to lufigenne = not he is to love, but he is to be loved.