% Example knowledge base for use with ASPIC Inference engine.
% created-on: 3rd November 2006
% created-by: MJS (matthew.south @ cancer.org.uk)

% An implementation of pollock's red light example

% try querying, "colour(X, Y)." 
% The argument that the ball is red is undercut by the fact that the ball is illuminated by a red light.

[appearance(Object, Colour)] colour(Object, Colour) <- looks(Object, Colour) 0.9.
~appearance(Object, Colour) <- illuminated(Object, Colour).
looks(ball, red).
looks(frisbee, green).
illuminated(ball, red).