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Isn't all this done by he himelf?
or
Isn't all this done by him himself?

Which is correct?
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Hello A Blinkin'

The preposition "by" demands an objective case so it should be "Isn't all this done by him himelf?"

paco
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The fixed expression you're talking about would occur with the active voice.

He did it by himself.

The by in the example sentence is a 'different' by, if you will. It is the by that introduces the agent of the action in passive voice.

It was done by him.

Or for emphasis, to say it was done directly by him and that he did not do it indirectly by assigning the task to others:

It was done by him himself.

You may think of this last example as a way of saying the following incorrect sentence:

*It was done by him by himself.

CJ
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Comments  
Shouldn't it be just by himself? Isn't this a fixed expression by + reflexive pronoun?
 CalifJim's reply was promoted to an answer.
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the first
He himselk
A Blinkin' Isn't all this done by he himelf?
or
Isn't all this done by him himself?

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