'********** variable unification 'If something can fly and eats worms, then it is a bird. <(&&,<$x --> flyer>,<(*,$x,worms) --> food>) ==> <$x --> bird>>. 'If something can fly, then it has wings. <<$y --> flyer> ==> <$y --> [with-wings]>>. ''//4 originally 13 'If something has wings and eats worms, then I guess it is a bird. ''outputMustContain('<(&&,<$1 --> [with-wings]>,<(*,$1,worms) --> food>) ==> <$1 --> bird>>. %1.00;0.45%')