0 used to refer to a male object of a verb that is the same person or animal as the subject of the verb: --
He's well enough in himself - he just can't shake this cold off.
Is Tom all right? He doesn't seem quite himself this morning.
Little Timmy made that snowman all by himself.
Tom was going to buy a bookcase, but in the end he made one himself.
Did you want to talk to the chairman himself, or could his personal assistant help you?
1 used to refer to an object of a verb that is the same person or animal as the subject of the verb, when referring to a person or animal whose sex is not known or not considered to be important: --