In fact, in this later, plainer work Roth often makes subtle poetry by using ordinary words in unexpected ways, or by mobilizing cliché, but he slips these phrases past us conversationally, almost before we have noticed them. … [In Exit Ghost,] Zuckerman reflects that he cannot defeat a much younger man, a literary journalist named Richard Kliman, who is ‘savage with health and armed to the teeth with time.’ It is wonderful to take the cliché 'armed to the teeth’ and combine it with the abstract word 'time,’ producing a hovering suggestion of a second cliché, this one having to do with old age, being 'long in the tooth.’ In this novel, and in this phrase, short in the tooth meets long in the tooth.
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Coming up with an expression like “armed to the teeth” is easy compared with fitting it into the style and narrative of a whole book. Of course, this isn’t a problem for P. Roth.