Which one is correct: "He is the taller of the two" or "He is taller of the two"
Solution 1:
The correct one is the one with the definite article. To prove this, I searched the Corpus of Contemporary American English.
I first searched BE the _jjr* of the two
(which finds examples that are a form of the verb "to be" followed by "the" followed by a comparative followed by "of the two") and got 110 results. Here's a screenshot of the forms it matched (limited to those that matched twice or more).
I also searched BE _jjr* of the two
(the same search without the direct article) and got one result.
The answer is clear: "the taller of the two" is correct because that's the form people use. You are referring to a specific previously mentioned person or thing, which is why the definite article fits.
Solution 2:
You could say :
Of the two, he is taller.
And it is difficult to say why that is more acceptable than :
He is taller of the two.
In the first above, there has been an identification 'the two'. Then comes a comparison 'taller'.
But in
He is taller of the two
the identification hangs in the air, waiting, as the comparison is being made.
It seems to me that our minds need to focus on something being identified, before we can compare it with something else and I think that is why one of the OP sentences is preferred above another.
[The other answer by @Laurel has already shown that there definitely is a preference.]
The first of the OP sentences contains (I would say) an ellipsis :
He is the taller [one] of the two.
I think the addition of the elliptical noun emphasises the identification being made and the reason for the sentence being preferred. The 'one' is identified out of the 'two'.