Q: Are the stative passive and the participial adjective the same construction? Examples: “He was born” … “I am surprised.” Is this a question of the existence (or mention) of the agent?
A: The general answer to both of your questions is a qualified yes: the constructions are similar, though not necessarily identical, and the presence of an “agent” does makes a difference.
But let me back up a bit and explain some of those terms for readers of The Grammarphobia Blog who may not be acquainted with them.
The issue you bring up has to do with the passive voice, something most of us are familiar with.
When a verb is in the active voice, the subject is the agent who does the acting (“John walks the dog regularly”).
But when the verb is in the passive voice, the object is the agent who does the acting (“The dog is walked by John regularly”), and the agent may even be omitted if the dog walker is irrelevant or unknown (“The dog is walked regularly”).
Notice that a sentence in the passive voice generally uses a form of the verb “be” as an auxiliary (in this case, “is”), and the verb is a past participle (“walked”).
Now, there are two kinds of passive voice, and this is where your question comes in. There’s the “dynamic” (also called actional) passive, and the “stative” (also called statal) passive.
The dynamic describes an event (“The dog was walked”), while the stative describes a state (“The dog was exhausted”). You might say that one denotes an act (expressed as a verb) and the other denotes the result of an act (expressed as a participial adjective).
Sometimes the difference between the two is very subtle. In his book A Grammar of the English Language. Vol. II: Syntax, George O. Curme gives this example: “The door was shut at six when I went by, but I don’t know when it was shut.”
The first “was shut” is a stative passive (denoting a state), and the second is a dynamic passive (denoting an act). Curme adds: “Thus the one form is employed to denote two quite different things.”
Rodney Huddleston and Geoffrey K. Pullum, in The Cambridge Grammar of the English Language, make a similar point when they discuss what they call “verbal passives” versus “adjectival passives.”
They use the example of “The vase was broken,” a sentence that could qualify for either definition. It could be interpreted as denoting either an event or the resulting state. In the first interpretation, “broken” is a verb, and in the second, “broken” is a participial adjective.
Elsewhere, Huddleston and Pullum note that there’s “a large-scale overlap between adjectives and the past participle forms of verbs, and since the verb be can take complements headed by either of these categories we find a significant resemblance, and often an ambiguity” between adjectives and past participles.
You ask whether the existence of an agent makes a difference. Generally, yes.
If an agent is mentioned (“I was surprised by Susan,” the passive form of the sentence “Susan surprised me”), then “surprised” can only be interpreted as a dynamic passive because it describes an event.
If no agent is mentioned (“I was surprised”), then “surprised” could be interpreted either as a passive verb or as an adjective describing a state.
I hope this helps. And I want to apologize to any readers of The Grammarphobia Blog who’ve been put off by all the technical talk.
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