Eckhard Bick - VISL

capable - by “negative instantiation” 222 - of discarding all prototypes in the bundle.
Prototype bundles are lumped together by CG set definitions, for instance:
LIST = @%inst ;
LIST = @%A @%AM @%AB @%zo @%D @%orn @%ent @%ich
As can be seen, the prototype forms a bundle of its own , while the
animal prototype bundle () consists of several sister prototypes.
For the prototype bundle, the list of “killing features”, i.e. of features
that - if discarded - disallows all prototypes in the bundle, is called in the
set-definition section of the parsers semantic CG module:
LIST = (@j @a @H @m @n @s @X @f @L @t) ; 223
Apart from the above mentioned H- and X- features (+HUM), the set includes -
MOVABLE (j), -ANIMATE (a), -MASS (m), +LOCATION (L) and others. The actual
prototype tag killing is performed by a simple CG rule:
REMOVE (NOT 0 )
Note that the basic type of this rule has no context conditions, only tag or set
membership conditions for the target itself. In practice, of course, a rule like the above
could be split up into individual rules for every target prototype and atomic feature
condition, and made more cautious or specific by adding real context conditions. Still,
the basic idea of the rule is not to establish a context, but rather to implement a kind of
feature inheritance reasoning, inferring one feature/tag from another: If a word form is
not A, then it cannot be B either. One could also say that the rule helps to express
(atomic) semantic feature information in terms of (complex) prototype bundles.
Due to the way atomic features are lumped into prototype bundles, certain
positive or negative atomic features imply certain others, and this, too, can be handled
by rules expressing feature inheritance reasoning. Atomic features, like prototypes, have
their own “killing sets”. In the prototype killing set only the essential, underivable,
atomic features are listed for the prototype bundle concerned (here ), but
information from other “secondary” features, is “translated” into disambiguation of
primary features by feature inheritance rules:
REMOVE (@=FEATURE) (0 @=feature) (NOT 0 ) ;
REMOVE (@=feature) (0 @=FEATURE) (NOT 0 ) ;
222 i.e. by not being true in a given context with a given set of CG rules.
223 With the present CG-compilers, @-tags (i.e. tags to be disambiguated on the same tag line) cannot be AND-ed as is the
case here. Rules involving contexts like must therefore be unfolded - at the latest, at compile time - into as many
individual rules as there are AND-ed features in the set concerned.
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