====== Birds ======
{{tag>knowledge_base}}
===== Description =====
Knowledge base for expert system which recognize birds

**Source**:  Building Expert Systems in PROLOG Publisher
===== Download =====
Program source code: {{birds.pl}}
===== Listing =====
<code prolog>
bird(laysan_albatross):-
family(albatross),
color(white).

bird(black_footed_albatross):-
family(albatross),
color(dark).

bird(whistling_swan) :-
family(swan),
voice(muffled_musical_whistle).

bird(trumpeter_swan) :-
family(swan),
voice(loud_trumpeting).
</code>
===== Comments =====