@prefix : <urn:example:> .
@prefix log: <http://www.w3.org/2000/10/swap/log#> .

(_:S1 _:V1 _:S2 _:V2) log:onNegativeSurface {
    _:S1 log:equalTo {
        (_:V1) log:onNeutralSurface {
            _:V1 a :C .
        } .
    } .
    _:S2 log:equalTo {
        (_:V2) log:onNeutralSurface {
            _:V2 a :C .
        } .
    } .
    _:S1 log:equalTo _:S2 .
    () log:onNegativeSurface {
        :test :is true .
    } .
} .

() log:onQuerySurface {
    :test :is true .
} .
