[DIG-users] Strange Inference Behaviour

[LECUE F. RD-TECH-R. <fre...@or...>]

Hi all,
  Suppose the following simple Knowledge Base wherein "Boy", "Person", =
"Man" and "HappyMan" are 4 concepts.

<impliesc>
<catom name=3D"Boy"/>
<catom name=3D"Person"/>
</impliesc>

<impliesc>
<catom name=3D"HappyMan"/>
<all>
<ratom name=3D"hasChild"/>
<catom name=3D"Boy"/>
</all>
</impliesc>

<impliesc>
<catom name=3D"Man"/>
<all>
<ratom name=3D"hasChild"/>
<catom name=3D"Person"/>
</all>
</impliesc>

  According to any reasoner (Fact++, cel) I use to interface the =
reasoning, when I ask if "Man" subsumes "HappyMan", the returned =
response is false!
  What do You think about this behaviour? Do you have any explanation?

Many thanks in advance.
Best,
Freddy