(The English sentence also has a generic or habitual reading, “Thetis loves mortals in general”, which we ignore here.) This interpretation has rather a classical look to it, but only because of the reduction from generalized to ordinary quantifiers that we have built into the lexical semantics of the indefinite a in the above rules, instead of using an atomic symbol for it. Montague was particularly interested in dealing satisfactorily with intensional locutions, such as  “John seeks a unicorn.” This does not require the existence of a unicorn for its truth—John has a certain relation to the unicorn-property, rather than to an existing unicorn. Montague therefore treated all predicate arguments as intensions; i.e., he rendered  “John seeks a unicorn” as