Analyzing the following expressions:
The expressions above are oxymorons, meaning that they put together words whose meaning are contrasting. We would assume that, if something or someone is pretty, they cannot be ugly; if something is true, it cannot be a lie.
That, however, is not the real purpose of this rhetorical device. The apparent contradiction mentioned above is precisely that: apparent. It does make sense in context because the first word serves as an intensifier of the second word.
We can observe that in the following examples:
In both instances, the first words of the oxymoron are intensifying the second one. The cut wasn't merely ugly, it was very ugly. "Pretty" does not keep its original meaning in this context.
The same happens with the word "true". The lies told were extremely obvious. "True" does not keep its original meaning either.
living dead
Clearly, living and dead are opposites, so it doesn't make sense to describe one being with both words. But we use this phrase to refer to imaginary monsters such as vampires and zombies because they are dead, but they retain some vestiges of life. For example, vampires can talk, and they can fly and scurry up walls. Zombies walk, make sounds, and eat. Both beings occupy a human body, although that body is not totally alive in the usual human sense. We also use the expression "living dead" metaphorically when we feel weary but can still go through the motions of life. It suggests we lack the spark that we associate with full-fledged living. The expression makes sense because it describes an imaginary state of existence that is somewhere between alive and dead and has some characteristics of both.
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