Relation as predicate name or predicate argument?

Discussion
#22

Reminds me of a talk in which a colleague reported correlations of correlations. A few years ago. I was wise enough not to attend it, but I guess P was below 0.05

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#23

Another advantage of using relation as predicate argument is that it can avoid discontiguous problem.

For example, if you only focus about the first person, you may prefer to write:

% mary's info
likes(mary, apple).
hates(mary, orange).

% peter's info
likes(peter, pear).
hates(peter, watermelon).

% alice's info
likes(alice, apple).
likes(alice, lemon).
hates(alice, banana).

instead of

likes(mary, apple).
likes(peter, pear).
likes(alice, apple).
likes(alice, lemon).

hates(alice, banana).
hates(peter, watermelon).
hates(mary, orange).

but SWI-Prolog will complain

Clauses of likes/2 are not together in the source-file... 
Use :- discontiguous likes/2. to suppress this message`.

There is no problem if you write:

% mary's info
x(mary, likes, apple).
x(mary, hates, orange).

% peter's info
x(peter, likes, pear).
x(peter, hates, watermelon).

% alice's info
x(alice, likes, apple).
x(alice, likes, lemon).
x(alice, hates, banana).

Here the relations are something like ā€œfieldsā€ in OOP.

Iā€™m not sure if this pattern (i.e. using relations to simulate OOP) has been widely used in LP community?

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#24

IMO this one is not a good enough reason to reify the relation that way, SWI-Prolog warns about discontiguous predicate definitions because by convention clauses of a single predicate are written contiguously and discontiguous definitions are often the result of a programmer error. Hence the compiler ā€œcomplainsā€.
If donā€™t want this convention to apply to one predicate or another, why not just use the :- discontiguous directive as suggested?