Following William Lycan's Philosophy of Language: a Contemporary Introduction, I will describe four puzzles which make the Theory of Reference appear untenable.
Puzzle #1 — Apparent Reference to Nonexistents
Zaphod Beeblebrox is two-headed.How can "Zaphod Beeblebrox" have meaning by standing in for something, if that 'something' doesn't exist? Lycan puts this intuition more explicitly (paraphrasing a bit):
I. The sentence above is meaningful.
II. The sentence above is in subject-predicate form.
III. A meaningful subject-predicate sentences is meaningful only because it refers to something then ascribes a quality to it.
IV. "Zaphod Beeblebrox" doesn't refer to anything that exists.
V. Given II through IV, the sentence above isn't meaningful...or it refers to something that doesn't exist.
VI. If something doesn't exist, it's impossible to refer to it.
One of the points from I to VI must be false. (Which would you challenge?)
Puzzle #2 — Negative Existentials
The Lemurian civilization never existed.Assuming this is true, how could it be a true, meaningful sentence under the Theory of Reference? The sentence explicitly denies the existence of the very thing it is supposedly pointing at and talking about, so to speak.
Puzzle #3 — Identity
Howard O'Brien is Anne Rice.If the Theory of Reference were correct, this should be a very boring, trivial, non-informative kind of statement along the lines of the equation x = x. There sure seems to be more information here than that! Probably even a commentary on her parents' psychology.
Puzzle #4 — Substitutivity
Debra Morgan knows that the Bay Harbor Butcher dismembers bodies.Since Dexter Morgan is the Bay Harbor Butcher, it should be possible to substitute referentially equivalent words without changing the meaning.
Debra Morgan knows that Dexter Morgan dismembers bodies.But she doesn't know this, at least not in the episodes I've seen. The two sentences obviously have very different meanings if one is true and the other false! (Leaving aside the question of whether facts about fictional characters are genuinely true, since real life cases are possible.)
The Theory of Reference is nice and simple, but doesn't work out. There are other theories which do a better job of capturing what we mean by 'meaning.' I don't think any of them has universal support among philosophers (what does?). And of course there's always the possibility our notion of 'meaning' isn't neat, so we can't ever capture it neatly.