When you use a comparative, you separate one individual from the rest. You compare a member of the group with any other member, or with all the other members. "This is better than the others," you say, or, "than any other."\
The comparative form of an adjective is frequently used to compare two people, things or states when you want to say that one thing has a larger or smaller amount of a quality than another. When mentioning the second part of the comparison, it follows than.
Why are these constructions illogical?:
"It is the most exciting detective story of any I have read."
"Nero was the most brutal of all the other Roman Emperors."
"It was the worst play as well as the most popular of all that had ever been performed in that theatre before."
"Lucy is lazier than all the girls in her class."
"She is handsomer than any women of her own age."
A detective story can't be the most exciting of any you have read, because "any" means "anyone," and a thing can't be the most exciting of one.
Nero can't have been the most brutal of all the other emperors because that group "other" doesn't include himself: saying that he was is as illogical as saying that the Johannesburg town hall is the highest building in Durban.
Similarly, a girl can't be prettier than any girl of her age, because she is a girl of her age, and she can't be prettier than herself: say "than any other girl of her age." Lucy can't be lazier than all the girls in her class because she can't be lazier than herself.
Be careful in making comparisons that you compare the things you mean to compare: for example, "Skirts are longer than last year" is a picturesque statement, but what the speaker probably meant was "Skirts are longer than they were last year," or, "Skirts are longer this year than last."
When you use a superlative you think in wholes, you consider a member of the group in relation to the whole group including himself. "This is the best of the lot," you say, or "He is the bravest of all."
