I ran into it last year when studying secondary literature on Shakespeare's Julius Caesar, a play which gives us the clearest example of what the word means. Illeism is the habit of speaking of oneself in the third person. The Latin "ille" means "that one," and one who speaks in this way is really an egotist. But, maybe not. When I was taught how to write papers, beginning way back in the third or fourth grade, I was always taught never to use the word "I." Why? I don't know, but perhaps it was a means of training little people to avoid the apparent subjectivity of the "I" by couching a statement in the seemingly more objective "he" or "they" or "we." But, as we see in Julius Caesar, Ceasar's use of his name in the third person can be an example of insufferable pride. So we have the quotation from Coleridge: "For one piece of egotism..there are fifty that steal out in the mask of tuisms and ille-isms." Or, as Blackwell's Magazine has it in 1832: "Your intense egotist avoids the use of the first person pronoun. He is, in fact, an Ille-ist." In our own day people who speak this way are more likely to use the first person plural. "We have decided," when in fact only one person has probably made the decision. Is this an example of "illeism"? I think so. We are trying to deflect potential criticism by distributing responsibilty to unnamed others.
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