Hence one of the semantic arguments ofeatalways corresponds to a syntactic argument, but the other may remain
implicit.
It is often said thateat“licenses an optional argument.”However, this conflates semantic and syntactic argument
structure. The character being eaten is part of one's understanding, whether it is expressed or not. This becomes
clearer by comparison with the verbswallow. Its syntactic behavior is identical to that ofeat: Bill swallowed (the food).But
although one cannot eat without eatingsomething, onecanswallow without swallowing anything. That is,swallowdiffers
fromeatin that its secondsemanticargument is optional.
The term“argument structure”refers to the specification of and relation between a word's semantic and syntactic
arguments. Differentiating the three verbs devour, eat, andswallowis in part a matter of assigning them different
argument structures. More generally, we need at least to be able to say how many semantic arguments a verb licenses,
and which of the mare obligatorily expressed.^62
Traditionally excluded fro margu ment structure are expressions of modification such as manner, time, and place
expressions. Certainly, if some event occurs, there is a time and place where it occurs. But verbs do not differ in
whether they allow expression of manner, time, and place: these are always optional.^63
134 ARCHITECTURAL FOUNDATIONS
(^62) Many languages, such as Korean and Japanese, are much freer than English in omitting arguments. In such languages there may be no justification for distinguishing
between obligatorily and optionally expressed semantic arguments.There is often an impulse to conjecture that the obligatoriness of arguments is predictable fro mthe
semantics. For instance,devouris more specific in its semantics thaneat, so perhaps more specific verbs tend to make their arguments obligatory. This conjecture is
immediately counterexemplified bycontrasts likeserve/give the food to Sallyvs.serve/give the food, whereservingis a more specific for mofgiving, andinsert/put the letter in the slot
vs.insert/put the letter, whereinsertingisa morespecificfor mofputting. Ialsonotetheverbsjuggleandflirt, whichhavegottobeamongthemorehighlyspecificverbsinthe
language, yet take an optional syntactic argument:juggle (six balls),flirt (with Kim). These arguments are not optional in semantics: one certainly can't juggle without juggling
something, norflirt withoutflirting with someone. I conclude that the obligatoriness of syntactic arguments must be encoded as an idiosyncratic lexical property.An
importantand little-mentioned distinctionamongimplicitsyntacticarguments is whethertheyare construed as“indefinite”or“definite.”For instance,theimplicitargument
inJohn is eatingisindefinite:itcanbeparaphrasedbyJohn is eating something. Bycontrast,theimplicitargumentinI'll show youisdefinite: therehas tobeanunderstooddiscourse
argument, and the explicit paraphrase isI'll show it to you. The choice between indefinite and definite implicitarguments seems specific to the verb (or possibly the semantic
verb class). See e.g. Grimshaw (1979), among others, for discussion of this distinction.
(^63) A cautionhere:Certain verbstake placeexpressions as obligatory syntacticarguments, e.g.Bill put the book on the table; certain verbstaketime expressions, e.g.The movie lasted
six hours;and certain verbs take manner expressions, e.g.Bill worded the letter carefully. The pointis that place,manner, and time arealways availableas optional additions to
semantically appropriate sentences.