Remove duplicate entry in README.md

README.md

@@ -429,98 +429,6 @@ and Anna's brothers, we can use the following function call:
     [{brother,bob,alice},{brother,mark,alice},{brother,caesar,anna}]
     8>
 
-Deriving new concepts by means of rules
----------------------------------------
-
-#### Concept: 'mother'
-
-The rule to derive the concept of mother is quite straightforward:
-
-    if X is female and X is Y's parent then X is Y's mother.
-
-From the point of view of SERESYE, since knowledge is stored in the
-*knowledge base* of the engine, the rule above is translated into the
-following one: *<u>if the facts *{female, X}* and *{parent, X, Y}* are
-**asserted** in the knowledge base, then we assert the fact *{mother,
-X, Y}*.</u>*
-
-The rule *mother* can be thus written as follows:
-
-
-    %%
-    %% if (X is female) and (X is Y's parent) then (X is Y's mother)
-    %%
-    mother(Engine, {female, X}, {parent, X, Y}) ->
-      seresye:assert(Engine, {mother, X, Y}).
-
-#### Concept: 'father'
-
-This concept can be easily derived by means of the following rule:
-
-    %%
-    %% if (X is male) and (X is Y's parent) then (X is Y's father)
-    %%
-    father(Engine, {male, X}, {parent, X, Y}) ->
-      seresye:assert(Engine, {father, X, Y}).
-
-
-#### Concept: 'sister'
-
-This concept can be expressed by the following rule:
-
-    if Y and Z have the same parent and Z is female, then Z is the Y's
-    sister.
-
-The SERESYE rule used to map this concept is:
-
-    %%
-    %% if (Y and Z have the same parent X) and (Z is female)
-    %%    then (Z is Y's sister)
-    %%
-    sister(Engine, {parent, X, Y}, {parent, X, Z}, {female, Z}) when Y =/= Z ->
-      seresye:assert(Engine, {sister, Z, Y}).
-
-Please note the guard, which is needed to ensure that when Y and Z are
-bound to the same value, the rule is not activated (indeed this is possible
-since the same fact can match both the first and second
-'parent' pattern).
-
-#### Concept: 'brother'
-
- Given the previous one, this concept is now quite simple to
-implement:
-
-    %%
-    %% if (Y and Z have the same parent X) and (Z is male)
-    %%    then (Z is Y's brother)
-    %%
-    brother(Engine, {parent, X, Y}, {parent, X, Z}, {male, Z}) when Y =/= Z ->
-      seresye:assert(Engine, {brother, Z, Y}).
-
-
-#### Concepts: 'grandmother' and 'grandfather'
-
-The former concept can be expressed by means of the rule:
-
-    if X is Y's mother and Y is Z's parent, then X is Z's grandmother.
-
-The latter concept is now obvious. Both can be implemented using the
-following SERESYE rules:
-
-    %%
-    %% if (X is Y's mother) and (Y is Z's parent)
-    %%    then (X is Z's grandmother)
-    %%
-    grandmother(Engine, {mother, X, Y}, {parent, Y, Z}) ->
-      seresye:assert(Engine, {grandmother, X, Z}).
-
-    %%
-    %% if (X is Y's father) and (Y is Z's parent)
-    %%    then (X is Z's grandfather)
-    %%
-    grandfather(Engine, {father, X, Y}, {parent, Y, Z}) ->
-      seresye:assert(Engine, {grandfather, X, Z}).
-
 
 Conclusions
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