Full Idea
People sometimes think that 'Socrates was a philosopher' expresses something like a true, singular proposition about Socrates. They're making a mistake, but still, this explains why they think it is true.
Gist of Idea
People are mistaken when they think 'Socrates was a philosopher' says something
Source
Ned Markosian (A Defense of Presentism [2004], 3.8)
Book Reference
'Persistence: contemporary readings', ed/tr. Haslanger,S/|Kurtz,RM [MIT 2006], p.322
A Reaction
A classic error theory, about our talk of the past. Personally I would say that the sentence really is true, and that needing a tangible object to refer to is a totally bogus requirement. 'I wonder if there are any scissors in the house?'