TSTP Solution File: PUZ031-1 by Metis---2.4

View Problem - Process Solution

%------------------------------------------------------------------------------
% File     : Metis---2.4
% Problem  : PUZ031-1 : TPTP v8.1.0. Released v1.0.0.
% Transfm  : none
% Format   : tptp:raw
% Command  : metis --show proof --show saturation %s

% Computer : n022.cluster.edu
% Model    : x86_64 x86_64
% CPU      : Intel(R) Xeon(R) CPU E5-2620 v4 2.10GHz
% Memory   : 8042.1875MB
% OS       : Linux 3.10.0-693.el7.x86_64
% CPULimit : 300s
% WCLimit  : 600s
% DateTime : Mon Jul 18 18:20:50 EDT 2022

% Result   : Unsatisfiable 0.13s 0.37s
% Output   : CNFRefutation 0.13s
% Verified : 
% SZS Type : Refutation
%            Derivation depth      :   28
%            Number of leaves      :   19
% Syntax   : Number of clauses     :   94 (  19 unt;  31 nHn;  94 RR)
%            Number of literals    :  287 (   0 equ; 170 neg)
%            Maximal clause size   :    8 (   3 avg)
%            Maximal term depth    :    2 (   1 avg)
%            Number of predicates  :   10 (   9 usr;   1 prp; 0-2 aty)
%            Number of functors    :    6 (   6 usr;   5 con; 0-1 aty)
%            Number of variables   :   71 (   0 sgn)

% Comments : 
%------------------------------------------------------------------------------
cnf(wolf_is_an_animal,axiom,
    ( animal(X)
    | ~ wolf(X) ) ).

cnf(fox_is_an_animal,axiom,
    ( animal(X)
    | ~ fox(X) ) ).

cnf(bird_is_an_animal,axiom,
    ( animal(X)
    | ~ bird(X) ) ).

cnf(snail_is_an_animal,axiom,
    ( animal(X)
    | ~ snail(X) ) ).

cnf(there_is_a_wolf,axiom,
    wolf(a_wolf) ).

cnf(there_is_a_fox,axiom,
    fox(a_fox) ).

cnf(there_is_a_bird,axiom,
    bird(a_bird) ).

cnf(there_is_a_snail,axiom,
    snail(a_snail) ).

cnf(there_is_a_grain,axiom,
    grain(a_grain) ).

cnf(grain_is_a_plant,axiom,
    ( plant(X)
    | ~ grain(X) ) ).

cnf(eating_habits,axiom,
    ( eats(Animal,Plant)
    | eats(Animal,Small_animal)
    | ~ animal(Animal)
    | ~ plant(Plant)
    | ~ animal(Small_animal)
    | ~ plant(Other_plant)
    | ~ much_smaller(Small_animal,Animal)
    | ~ eats(Small_animal,Other_plant) ) ).

cnf(snail_smaller_than_bird,axiom,
    ( much_smaller(Snail,Bird)
    | ~ snail(Snail)
    | ~ bird(Bird) ) ).

cnf(bird_smaller_than_fox,axiom,
    ( much_smaller(Bird,Fox)
    | ~ bird(Bird)
    | ~ fox(Fox) ) ).

cnf(fox_smaller_than_wolf,axiom,
    ( much_smaller(Fox,Wolf)
    | ~ fox(Fox)
    | ~ wolf(Wolf) ) ).

cnf(wolf_dont_eat_grain,axiom,
    ( ~ wolf(Wolf)
    | ~ grain(Grain)
    | ~ eats(Wolf,Grain) ) ).

cnf(bird_dont_eat_snail,axiom,
    ( ~ bird(Bird)
    | ~ snail(Snail)
    | ~ eats(Bird,Snail) ) ).

cnf(snail_food_is_a_plant,axiom,
    ( plant(snail_food_of(Snail))
    | ~ snail(Snail) ) ).

cnf(snail_eats_snail_food,axiom,
    ( eats(Snail,snail_food_of(Snail))
    | ~ snail(Snail) ) ).

cnf(prove_the_animal_exists,negated_conjecture,
    ( ~ animal(Animal)
    | ~ animal(Grain_eater)
    | ~ grain(Grain)
    | ~ eats(Animal,Grain_eater)
    | ~ eats(Grain_eater,Grain) ) ).

cnf(refute_0_0,plain,
    ( ~ animal(Animal)
    | ~ animal(a_bird)
    | ~ eats(Animal,a_bird)
    | ~ eats(a_bird,a_grain)
    | ~ grain(a_grain) ),
    inference(subst,[],[prove_the_animal_exists:[bind(Grain,$fot(a_grain)),bind(Grain_eater,$fot(a_bird))]]) ).

cnf(refute_0_1,plain,
    ( ~ bird(a_bird)
    | ~ eats(a_bird,a_snail)
    | ~ snail(a_snail) ),
    inference(subst,[],[bird_dont_eat_snail:[bind(Bird,$fot(a_bird)),bind(Snail,$fot(a_snail))]]) ).

cnf(refute_0_2,plain,
    ( ~ grain(a_grain)
    | plant(a_grain) ),
    inference(subst,[],[grain_is_a_plant:[bind(X,$fot(a_grain))]]) ).

cnf(refute_0_3,plain,
    plant(a_grain),
    inference(resolve,[$cnf( grain(a_grain) )],[there_is_a_grain,refute_0_2]) ).

cnf(refute_0_4,plain,
    ( ~ bird(X_18)
    | ~ snail(a_snail)
    | much_smaller(a_snail,X_18) ),
    inference(subst,[],[snail_smaller_than_bird:[bind(Bird,$fot(X_18)),bind(Snail,$fot(a_snail))]]) ).

cnf(refute_0_5,plain,
    ( ~ bird(X_18)
    | much_smaller(a_snail,X_18) ),
    inference(resolve,[$cnf( snail(a_snail) )],[there_is_a_snail,refute_0_4]) ).

cnf(refute_0_6,plain,
    ( ~ bird(a_bird)
    | much_smaller(a_snail,a_bird) ),
    inference(subst,[],[refute_0_5:[bind(X_18,$fot(a_bird))]]) ).

cnf(refute_0_7,plain,
    much_smaller(a_snail,a_bird),
    inference(resolve,[$cnf( bird(a_bird) )],[there_is_a_bird,refute_0_6]) ).

cnf(refute_0_8,plain,
    ( ~ snail(a_snail)
    | eats(a_snail,snail_food_of(a_snail)) ),
    inference(subst,[],[snail_eats_snail_food:[bind(Snail,$fot(a_snail))]]) ).

cnf(refute_0_9,plain,
    eats(a_snail,snail_food_of(a_snail)),
    inference(resolve,[$cnf( snail(a_snail) )],[there_is_a_snail,refute_0_8]) ).

cnf(refute_0_10,plain,
    ( ~ animal(X_38)
    | ~ animal(a_snail)
    | ~ eats(a_snail,snail_food_of(a_snail))
    | ~ much_smaller(a_snail,X_38)
    | ~ plant(X_40)
    | ~ plant(snail_food_of(a_snail))
    | eats(X_38,X_40)
    | eats(X_38,a_snail) ),
    inference(subst,[],[eating_habits:[bind(Animal,$fot(X_38)),bind(Other_plant,$fot(snail_food_of(a_snail))),bind(Plant,$fot(X_40)),bind(Small_animal,$fot(a_snail))]]) ).

cnf(refute_0_11,plain,
    ( ~ animal(X_38)
    | ~ animal(a_snail)
    | ~ much_smaller(a_snail,X_38)
    | ~ plant(X_40)
    | ~ plant(snail_food_of(a_snail))
    | eats(X_38,X_40)
    | eats(X_38,a_snail) ),
    inference(resolve,[$cnf( eats(a_snail,snail_food_of(a_snail)) )],[refute_0_9,refute_0_10]) ).

cnf(refute_0_12,plain,
    ( ~ snail(a_snail)
    | animal(a_snail) ),
    inference(subst,[],[snail_is_an_animal:[bind(X,$fot(a_snail))]]) ).

cnf(refute_0_13,plain,
    animal(a_snail),
    inference(resolve,[$cnf( snail(a_snail) )],[there_is_a_snail,refute_0_12]) ).

cnf(refute_0_14,plain,
    ( ~ animal(X_38)
    | ~ much_smaller(a_snail,X_38)
    | ~ plant(X_40)
    | ~ plant(snail_food_of(a_snail))
    | eats(X_38,X_40)
    | eats(X_38,a_snail) ),
    inference(resolve,[$cnf( animal(a_snail) )],[refute_0_13,refute_0_11]) ).

cnf(refute_0_15,plain,
    ( ~ snail(a_snail)
    | plant(snail_food_of(a_snail)) ),
    inference(subst,[],[snail_food_is_a_plant:[bind(Snail,$fot(a_snail))]]) ).

cnf(refute_0_16,plain,
    plant(snail_food_of(a_snail)),
    inference(resolve,[$cnf( snail(a_snail) )],[there_is_a_snail,refute_0_15]) ).

cnf(refute_0_17,plain,
    ( ~ animal(X_38)
    | ~ much_smaller(a_snail,X_38)
    | ~ plant(X_40)
    | eats(X_38,X_40)
    | eats(X_38,a_snail) ),
    inference(resolve,[$cnf( plant(snail_food_of(a_snail)) )],[refute_0_16,refute_0_14]) ).

cnf(refute_0_18,plain,
    ( ~ animal(a_bird)
    | ~ much_smaller(a_snail,a_bird)
    | ~ plant(X_45)
    | eats(a_bird,X_45)
    | eats(a_bird,a_snail) ),
    inference(subst,[],[refute_0_17:[bind(X_38,$fot(a_bird)),bind(X_40,$fot(X_45))]]) ).

cnf(refute_0_19,plain,
    ( ~ animal(a_bird)
    | ~ plant(X_45)
    | eats(a_bird,X_45)
    | eats(a_bird,a_snail) ),
    inference(resolve,[$cnf( much_smaller(a_snail,a_bird) )],[refute_0_7,refute_0_18]) ).

cnf(refute_0_20,plain,
    ( ~ bird(a_bird)
    | animal(a_bird) ),
    inference(subst,[],[bird_is_an_animal:[bind(X,$fot(a_bird))]]) ).

cnf(refute_0_21,plain,
    animal(a_bird),
    inference(resolve,[$cnf( bird(a_bird) )],[there_is_a_bird,refute_0_20]) ).

cnf(refute_0_22,plain,
    ( ~ plant(X_45)
    | eats(a_bird,X_45)
    | eats(a_bird,a_snail) ),
    inference(resolve,[$cnf( animal(a_bird) )],[refute_0_21,refute_0_19]) ).

cnf(refute_0_23,plain,
    ( ~ plant(a_grain)
    | eats(a_bird,a_grain)
    | eats(a_bird,a_snail) ),
    inference(subst,[],[refute_0_22:[bind(X_45,$fot(a_grain))]]) ).

cnf(refute_0_24,plain,
    ( eats(a_bird,a_grain)
    | eats(a_bird,a_snail) ),
    inference(resolve,[$cnf( plant(a_grain) )],[refute_0_3,refute_0_23]) ).

cnf(refute_0_25,plain,
    ( ~ bird(a_bird)
    | ~ snail(a_snail)
    | eats(a_bird,a_grain) ),
    inference(resolve,[$cnf( eats(a_bird,a_snail) )],[refute_0_24,refute_0_1]) ).

cnf(refute_0_26,plain,
    ( ~ snail(a_snail)
    | eats(a_bird,a_grain) ),
    inference(resolve,[$cnf( bird(a_bird) )],[there_is_a_bird,refute_0_25]) ).

cnf(refute_0_27,plain,
    eats(a_bird,a_grain),
    inference(resolve,[$cnf( snail(a_snail) )],[there_is_a_snail,refute_0_26]) ).

cnf(refute_0_28,plain,
    ( ~ animal(Animal)
    | ~ animal(a_bird)
    | ~ eats(Animal,a_bird)
    | ~ grain(a_grain) ),
    inference(resolve,[$cnf( eats(a_bird,a_grain) )],[refute_0_27,refute_0_0]) ).

cnf(refute_0_29,plain,
    ( ~ animal(Animal)
    | ~ eats(Animal,a_bird)
    | ~ grain(a_grain) ),
    inference(resolve,[$cnf( animal(a_bird) )],[refute_0_21,refute_0_28]) ).

cnf(refute_0_30,plain,
    ( ~ animal(Animal)
    | ~ eats(Animal,a_bird) ),
    inference(resolve,[$cnf( grain(a_grain) )],[there_is_a_grain,refute_0_29]) ).

cnf(refute_0_31,plain,
    ( ~ animal(a_fox)
    | ~ eats(a_fox,a_bird) ),
    inference(subst,[],[refute_0_30:[bind(Animal,$fot(a_fox))]]) ).

cnf(refute_0_32,plain,
    ( ~ animal(Animal)
    | ~ animal(a_fox)
    | ~ eats(Animal,a_fox)
    | ~ eats(a_fox,a_grain)
    | ~ grain(a_grain) ),
    inference(subst,[],[prove_the_animal_exists:[bind(Grain,$fot(a_grain)),bind(Grain_eater,$fot(a_fox))]]) ).

cnf(refute_0_33,plain,
    ( ~ bird(X_21)
    | ~ fox(a_fox)
    | much_smaller(X_21,a_fox) ),
    inference(subst,[],[bird_smaller_than_fox:[bind(Bird,$fot(X_21)),bind(Fox,$fot(a_fox))]]) ).

cnf(refute_0_34,plain,
    ( ~ bird(X_21)
    | much_smaller(X_21,a_fox) ),
    inference(resolve,[$cnf( fox(a_fox) )],[there_is_a_fox,refute_0_33]) ).

cnf(refute_0_35,plain,
    ( ~ bird(a_bird)
    | much_smaller(a_bird,a_fox) ),
    inference(subst,[],[refute_0_34:[bind(X_21,$fot(a_bird))]]) ).

cnf(refute_0_36,plain,
    much_smaller(a_bird,a_fox),
    inference(resolve,[$cnf( bird(a_bird) )],[there_is_a_bird,refute_0_35]) ).

cnf(refute_0_37,plain,
    ( ~ animal(a_bird)
    | ~ animal(a_fox)
    | ~ eats(a_bird,X_39)
    | ~ much_smaller(a_bird,a_fox)
    | ~ plant(X_39)
    | ~ plant(X_40)
    | eats(a_fox,X_40)
    | eats(a_fox,a_bird) ),
    inference(subst,[],[eating_habits:[bind(Animal,$fot(a_fox)),bind(Other_plant,$fot(X_39)),bind(Plant,$fot(X_40)),bind(Small_animal,$fot(a_bird))]]) ).

cnf(refute_0_38,plain,
    ( ~ animal(a_bird)
    | ~ animal(a_fox)
    | ~ eats(a_bird,X_39)
    | ~ plant(X_39)
    | ~ plant(X_40)
    | eats(a_fox,X_40)
    | eats(a_fox,a_bird) ),
    inference(resolve,[$cnf( much_smaller(a_bird,a_fox) )],[refute_0_36,refute_0_37]) ).

cnf(refute_0_39,plain,
    ( ~ animal(a_fox)
    | ~ eats(a_bird,X_39)
    | ~ plant(X_39)
    | ~ plant(X_40)
    | eats(a_fox,X_40)
    | eats(a_fox,a_bird) ),
    inference(resolve,[$cnf( animal(a_bird) )],[refute_0_21,refute_0_38]) ).

cnf(refute_0_40,plain,
    ( ~ fox(a_fox)
    | animal(a_fox) ),
    inference(subst,[],[fox_is_an_animal:[bind(X,$fot(a_fox))]]) ).

cnf(refute_0_41,plain,
    animal(a_fox),
    inference(resolve,[$cnf( fox(a_fox) )],[there_is_a_fox,refute_0_40]) ).

cnf(refute_0_42,plain,
    ( ~ eats(a_bird,X_39)
    | ~ plant(X_39)
    | ~ plant(X_40)
    | eats(a_fox,X_40)
    | eats(a_fox,a_bird) ),
    inference(resolve,[$cnf( animal(a_fox) )],[refute_0_41,refute_0_39]) ).

cnf(refute_0_43,plain,
    ( ~ eats(a_bird,a_grain)
    | ~ plant(X_49)
    | ~ plant(a_grain)
    | eats(a_fox,X_49)
    | eats(a_fox,a_bird) ),
    inference(subst,[],[refute_0_42:[bind(X_39,$fot(a_grain)),bind(X_40,$fot(X_49))]]) ).

cnf(refute_0_44,plain,
    ( ~ plant(X_49)
    | ~ plant(a_grain)
    | eats(a_fox,X_49)
    | eats(a_fox,a_bird) ),
    inference(resolve,[$cnf( eats(a_bird,a_grain) )],[refute_0_27,refute_0_43]) ).

cnf(refute_0_45,plain,
    ( ~ plant(X_49)
    | eats(a_fox,X_49)
    | eats(a_fox,a_bird) ),
    inference(resolve,[$cnf( plant(a_grain) )],[refute_0_3,refute_0_44]) ).

cnf(refute_0_46,plain,
    ( ~ plant(a_grain)
    | eats(a_fox,a_bird)
    | eats(a_fox,a_grain) ),
    inference(subst,[],[refute_0_45:[bind(X_49,$fot(a_grain))]]) ).

cnf(refute_0_47,plain,
    ( eats(a_fox,a_bird)
    | eats(a_fox,a_grain) ),
    inference(resolve,[$cnf( plant(a_grain) )],[refute_0_3,refute_0_46]) ).

cnf(refute_0_48,plain,
    ( ~ animal(Animal)
    | ~ animal(a_fox)
    | ~ eats(Animal,a_fox)
    | ~ grain(a_grain)
    | eats(a_fox,a_bird) ),
    inference(resolve,[$cnf( eats(a_fox,a_grain) )],[refute_0_47,refute_0_32]) ).

cnf(refute_0_49,plain,
    ( ~ animal(Animal)
    | ~ eats(Animal,a_fox)
    | ~ grain(a_grain)
    | eats(a_fox,a_bird) ),
    inference(resolve,[$cnf( animal(a_fox) )],[refute_0_41,refute_0_48]) ).

cnf(refute_0_50,plain,
    ( ~ animal(Animal)
    | ~ eats(Animal,a_fox)
    | eats(a_fox,a_bird) ),
    inference(resolve,[$cnf( grain(a_grain) )],[there_is_a_grain,refute_0_49]) ).

cnf(refute_0_51,plain,
    ( ~ animal(a_wolf)
    | ~ eats(a_wolf,a_fox)
    | eats(a_fox,a_bird) ),
    inference(subst,[],[refute_0_50:[bind(Animal,$fot(a_wolf))]]) ).

cnf(refute_0_52,plain,
    ( ~ eats(a_wolf,a_grain)
    | ~ grain(a_grain)
    | ~ wolf(a_wolf) ),
    inference(subst,[],[wolf_dont_eat_grain:[bind(Grain,$fot(a_grain)),bind(Wolf,$fot(a_wolf))]]) ).

cnf(refute_0_53,plain,
    ( ~ fox(X_24)
    | ~ wolf(a_wolf)
    | much_smaller(X_24,a_wolf) ),
    inference(subst,[],[fox_smaller_than_wolf:[bind(Fox,$fot(X_24)),bind(Wolf,$fot(a_wolf))]]) ).

cnf(refute_0_54,plain,
    ( ~ fox(X_24)
    | much_smaller(X_24,a_wolf) ),
    inference(resolve,[$cnf( wolf(a_wolf) )],[there_is_a_wolf,refute_0_53]) ).

cnf(refute_0_55,plain,
    ( ~ fox(a_fox)
    | much_smaller(a_fox,a_wolf) ),
    inference(subst,[],[refute_0_54:[bind(X_24,$fot(a_fox))]]) ).

cnf(refute_0_56,plain,
    much_smaller(a_fox,a_wolf),
    inference(resolve,[$cnf( fox(a_fox) )],[there_is_a_fox,refute_0_55]) ).

cnf(refute_0_57,plain,
    ( ~ animal(a_fox)
    | ~ animal(a_wolf)
    | ~ eats(a_fox,X_39)
    | ~ much_smaller(a_fox,a_wolf)
    | ~ plant(X_39)
    | ~ plant(X_40)
    | eats(a_wolf,X_40)
    | eats(a_wolf,a_fox) ),
    inference(subst,[],[eating_habits:[bind(Animal,$fot(a_wolf)),bind(Other_plant,$fot(X_39)),bind(Plant,$fot(X_40)),bind(Small_animal,$fot(a_fox))]]) ).

cnf(refute_0_58,plain,
    ( ~ animal(a_fox)
    | ~ animal(a_wolf)
    | ~ eats(a_fox,X_39)
    | ~ plant(X_39)
    | ~ plant(X_40)
    | eats(a_wolf,X_40)
    | eats(a_wolf,a_fox) ),
    inference(resolve,[$cnf( much_smaller(a_fox,a_wolf) )],[refute_0_56,refute_0_57]) ).

cnf(refute_0_59,plain,
    ( ~ animal(a_wolf)
    | ~ eats(a_fox,X_39)
    | ~ plant(X_39)
    | ~ plant(X_40)
    | eats(a_wolf,X_40)
    | eats(a_wolf,a_fox) ),
    inference(resolve,[$cnf( animal(a_fox) )],[refute_0_41,refute_0_58]) ).

cnf(refute_0_60,plain,
    ( ~ wolf(a_wolf)
    | animal(a_wolf) ),
    inference(subst,[],[wolf_is_an_animal:[bind(X,$fot(a_wolf))]]) ).

cnf(refute_0_61,plain,
    animal(a_wolf),
    inference(resolve,[$cnf( wolf(a_wolf) )],[there_is_a_wolf,refute_0_60]) ).

cnf(refute_0_62,plain,
    ( ~ eats(a_fox,X_39)
    | ~ plant(X_39)
    | ~ plant(X_40)
    | eats(a_wolf,X_40)
    | eats(a_wolf,a_fox) ),
    inference(resolve,[$cnf( animal(a_wolf) )],[refute_0_61,refute_0_59]) ).

cnf(refute_0_63,plain,
    ( ~ eats(a_fox,a_grain)
    | ~ plant(X_53)
    | ~ plant(a_grain)
    | eats(a_wolf,X_53)
    | eats(a_wolf,a_fox) ),
    inference(subst,[],[refute_0_62:[bind(X_39,$fot(a_grain)),bind(X_40,$fot(X_53))]]) ).

cnf(refute_0_64,plain,
    ( ~ plant(X_53)
    | ~ plant(a_grain)
    | eats(a_fox,a_bird)
    | eats(a_wolf,X_53)
    | eats(a_wolf,a_fox) ),
    inference(resolve,[$cnf( eats(a_fox,a_grain) )],[refute_0_47,refute_0_63]) ).

cnf(refute_0_65,plain,
    ( ~ plant(X_53)
    | eats(a_fox,a_bird)
    | eats(a_wolf,X_53)
    | eats(a_wolf,a_fox) ),
    inference(resolve,[$cnf( plant(a_grain) )],[refute_0_3,refute_0_64]) ).

cnf(refute_0_66,plain,
    ( ~ plant(a_grain)
    | eats(a_fox,a_bird)
    | eats(a_wolf,a_fox)
    | eats(a_wolf,a_grain) ),
    inference(subst,[],[refute_0_65:[bind(X_53,$fot(a_grain))]]) ).

cnf(refute_0_67,plain,
    ( eats(a_fox,a_bird)
    | eats(a_wolf,a_fox)
    | eats(a_wolf,a_grain) ),
    inference(resolve,[$cnf( plant(a_grain) )],[refute_0_3,refute_0_66]) ).

cnf(refute_0_68,plain,
    ( ~ grain(a_grain)
    | ~ wolf(a_wolf)
    | eats(a_fox,a_bird)
    | eats(a_wolf,a_fox) ),
    inference(resolve,[$cnf( eats(a_wolf,a_grain) )],[refute_0_67,refute_0_52]) ).

cnf(refute_0_69,plain,
    ( ~ wolf(a_wolf)
    | eats(a_fox,a_bird)
    | eats(a_wolf,a_fox) ),
    inference(resolve,[$cnf( grain(a_grain) )],[there_is_a_grain,refute_0_68]) ).

cnf(refute_0_70,plain,
    ( eats(a_fox,a_bird)
    | eats(a_wolf,a_fox) ),
    inference(resolve,[$cnf( wolf(a_wolf) )],[there_is_a_wolf,refute_0_69]) ).

cnf(refute_0_71,plain,
    ( ~ animal(a_wolf)
    | eats(a_fox,a_bird) ),
    inference(resolve,[$cnf( eats(a_wolf,a_fox) )],[refute_0_70,refute_0_51]) ).

cnf(refute_0_72,plain,
    eats(a_fox,a_bird),
    inference(resolve,[$cnf( animal(a_wolf) )],[refute_0_61,refute_0_71]) ).

cnf(refute_0_73,plain,
    ~ animal(a_fox),
    inference(resolve,[$cnf( eats(a_fox,a_bird) )],[refute_0_72,refute_0_31]) ).

cnf(refute_0_74,plain,
    $false,
    inference(resolve,[$cnf( animal(a_fox) )],[refute_0_41,refute_0_73]) ).

%------------------------------------------------------------------------------
%----ORIGINAL SYSTEM OUTPUT
% 0.12/0.12  % Problem  : PUZ031-1 : TPTP v8.1.0. Released v1.0.0.
% 0.12/0.13  % Command  : metis --show proof --show saturation %s
% 0.13/0.34  % Computer : n022.cluster.edu
% 0.13/0.34  % Model    : x86_64 x86_64
% 0.13/0.34  % CPU      : Intel(R) Xeon(R) CPU E5-2620 v4 @ 2.10GHz
% 0.13/0.34  % Memory   : 8042.1875MB
% 0.13/0.34  % OS       : Linux 3.10.0-693.el7.x86_64
% 0.13/0.34  % CPULimit : 300
% 0.13/0.34  % WCLimit  : 600
% 0.13/0.34  % DateTime : Sat May 28 22:25:53 EDT 2022
% 0.13/0.35  % CPUTime  : 
% 0.13/0.35  %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% 0.13/0.37  % SZS status Unsatisfiable for /export/starexec/sandbox2/benchmark/theBenchmark.p
% 0.13/0.37  
% 0.13/0.37  % SZS output start CNFRefutation for /export/starexec/sandbox2/benchmark/theBenchmark.p
% See solution above
% 0.13/0.38  
%------------------------------------------------------------------------------