I don't understand

[bruno patin]

My first contact with the reality of a prolog tool so excuse me for my
question who I think is ridiculous.

When I load the file new_main.pl from the ExampleC, there is no problem.
When at the top level I try to write the first definition, that is,
"parent(bob,mary).", I have the error :uncaught exception:
error(existence_error(procedure,parent/2),top_level/0)

I think I don't know how to init the tool but I don't understand why it is
different when I load the file.

thank you for your help

bruno