A simple knowledge base for identifying animals.

Source: PROLOG programming for artificial intelligence, 3rd Edition, Harlow, 2001, ISBN 0-201-40375-7.

Program source code: animals_kb.pl

% Figure 16.1  A simple knowledge base for identifying animals.
 
% Adapted from Winston (1984). The relation 'askable' defines those things
 
% that can be asked by user. The operators '::', if, then, 'and', 'or'
 
% are declared as in Figure 16.6.
 
 
 
 
 
%     A small knowledge base for identifying animals
 
 
 
:-  op( 100, xfx, [ has, gives, 'does not', eats, lays, isa]).
 
 
 
:-  op( 100, xf, [ swims, flies]).
 
:-  op( 200, xfy, [:, ::]).
 
:-  op( 185, fx, if).
 
:-  op( 190, xfx, then).
 
:-  op( 180, xfy, or).
 
:-  op( 160, xfy, and).
 
 
 
 
 
rule1 ::   if
 
		Animal has hair
 
	   or
 
		Animal gives milk
 
	then
 
		Animal isa mammal.
 
 
 
 
 
rule2 ::   if
 
		Animal has feathers
 
	   or
 
		Animal flies  and
 
		Animal lays eggs
 
	then
 
		Animal isa bird.
 
 
 
rule3 ::  if
 
		Animal isa mammal  and
 
              ( Animal eats meat
 
                  or
 
		Animal has 'pointed teeth' and
 
		Animal has claws  and
 
		Animal has 'forward pointing eyes' )
 
	then
 
		Animal isa carnivore.
 
 
 
rule4 ::  if
 
		Animal isa carnivore  and
 
		Animal has 'tawny color'  and
 
		Animal has 'dark spots'
 
        then
 
		Animal isa cheetah.
 
 
 
rule5 ::  if
 
		Animal isa carnivore  and
 
		Animal has 'tawny color'  and
 
		Animal has 'black stripes'
 
	then
 
		Animal isa tiger.
 
 
 
rule6 ::  if
 
		Animal isa bird  and
 
		Animal 'does not' fly  and
 
		Animal swims
 
	then
 
		Animal isa penguin.
 
 
 
rule7 :: if
 
		Animal isa bird  and
 
		Animal isa 'good flyer'
 
	then
 
		Animal isa albatross.
 
 
 
 
 
fact :: X isa animal   :-
 
  member( X, [cheetah, tiger, penguin, albatross]).
 
 
 
 
 
askable( _ gives _, 'Animal' gives 'What').
 
 
 
askable( _ flies, 'Animal' flies).
 
 
 
askable( _ lays eggs, 'Animal' lays eggs).
 
 
 
askable( _ eats _, 'Animal' eats 'What').
 
 
 
askable( _ has _, 'Animal' has 'Something').
 
 
 
askable( _ 'does not' _, 'Animal' 'does not' fly).
 
 
 
askable( _ swims, 'Animal' swims).
 
 
 
askable( _ isa 'good flyer', 'Animal' isa 'good flyer').