in the Lexicon ({the, book}). Under the formulation in (15), however, Search 0
fails to do this: if it takes the Lexicon as an input, it cannot pick out {the, book},
while if it takes this SO as an input, it cannot pick out read. Thus, we propose
to revise the formulation of Search 0 further in the following way:
(18) Search 0 (fi nal version)
Search 0 is an operation that picks out n elements contained in the work-
space (WS).
We assume that WS is the set consisting of SOs already constructed and LIs in the
Lexicon, that is, WS = {Σ 1 ,.. ., Σn} ∪ Lexicon = {Σ 1 ,.. ., Σn, LI 1 ,.. ., LIm} (note
that the Lexicon is the set of LIs, which we tentatively take to be fi nite). Refor-
mulated as in (18), Search 0 can now pick out an LI and a non-LI SO Σ, since
both of them are contained in WS. Thus, M 0 ◦S 0 (WS) can work as shown below.
(19) M 0 ◦S 0 (WS) = {Σ, LI}
We argue that this is what happens in (17): Search 0 applies to WS = {{the, book},
LI 1 ,.. ., read,.. ., LIm} and picks out read and {the, book}; Merge 0 applies to
these objects and forms a set {read, {the, book}}.
Search 0 as formulated in (18) can also pick out two non-LI SOs Σi, Σj con-
tained in WS. In that case M 0 ◦S 0 (WS) = {Σi, Σj}. This takes place, for example,
in the EM of {the, woman} and {v, {criticize, John}} to form vP:
(20) {the, woman} ← EM → {v, {criticize, John}}
Search 0 applies to WS = {{the, woman}, {v, {criticize, John}}, LI 1 ,.. ., LIm} and
picks out {the, woman} and {v,{criticize, John}}; Merge 0 applies to these objects
and forms a set {{the, woman}, {v,{criticize, John}}}.
To sum up the discussion in this section and the previous one: we have
proposed that the Search operation of Kato et al. (2014) ought to be regarded
as a composition of the two more primitive operations, Search 0 and Merge 0 ,
which we notate as M 0 ◦S 0. Search 0 picks out n objects and Merge 0 forms the
set of these objects. Under the proposed mechanism, labeling is naturally unifi ed
with other operations such as Agree, binding and chain-formation. We have
also shown that Merge can also be regarded as an instance of M 0 ◦S 0 by modify-
ing the formulation of Search 0 so that M 0 ◦S 0 takes WS as an input. If the dis-
cussion so far is on the right track, all the syntactic operations are unifi ed under
M 0 ◦S 0 (WS), a welcome result from a minimalist perspective.
4 Refi ning the notion of occurrence
In the preceding discussion, we established that Merge and Search, as well as
labeling (Chomsky 2005, 2007, 2008), can be uniformly characterized as M◦S(WS).
We specifi cally hypothesized that Merge 0 always yields an unordered set in every
case, regardless of whether the result is chain-formation, Agree, labeling or
On the primitive operations of syntax 35