How do you assign Case to sentences with an infinitival clause?

Question

Look at this example: For the butler to attack the robber would be surprising. Here, the butler and the robber are assigned accusative case. Is 'for' assigning case to the butler and 'to attack' assigning case to the robber? Doesn't there need to be a subject in the clause, so there's something with nominative case? Am I right in saying 'to attack' does not assign the nominative case to anything? For sentences such as: 'That the butler attacked the robber is surprising.' I understand the case assigning, attacked assigns nom. to the butler and acc. to the robber. As soon as an infinitival clause gets involved, I find myself getting very confused. Can anyone help?

Answer 1

You are certainly correct that "to attack" assigns objective case to "robber" and does not assign subjective case to anything. The assignment of case to "butler" depends on how you construe the surrounding elements:

1) You can consider that the object of the preposition "for" is the small clause "the butler to attack the robber". In this case, "butler", though the subject of the small clause, would be in the objective case because it is controlled by the preposition "for". (Object control usually involves a control verb, but in this case there is a control preposition.)

2) You can consider that the object of the preposition "for" is simply the noun "butler". In this case, "to attack the robber" is a complementary infinitive phrase, and the sentence has no subordinate clause.

This is a pretty unusual sentence, and others might have other thoughts about how to parse it, but I hope that this helps.