# [Prolog] How do I implement recursion in Prolog?

To implement recursion in Prolog, you can define rules that call themselves until a certain condition is met. Here's an example of how to implement recursion in Prolog:

```
1% Define a base case for the recursion
2recursive_predicate(0).
3
4% Define a rule that calls itself until the base case is met
5recursive_predicate(N) :-
6 N > 0,
7 Next is N - 1,
8 recursive_predicate(Next).
```

In this example, `recursive_predicate`

is a predicate that takes an argument `N`

. The base case is defined as when `N`

equals 0. The recursive rule is defined as when `N`

is greater than 0, it subtracts 1 from `N`

and calls `recursive_predicate`

again with the new value. This process continues until the base case is met.

You can then query the predicate with different values of `N`

to see the recursive behavior. For example:

```
1?- recursive_predicate(3).
2true.
3
4?- recursive_predicate(5).
5true.
6
7?- recursive_predicate(0).
8true.
9
10?- recursive_predicate(-1).
11false.
```

In this case, `recursive_predicate(3)`

and `recursive_predicate(5)`

are both true because 3 and 5 can be reduced to 0 through the recursive rule. On the other hand, `recursive_predicate(0)`

is true because it matches the base case. Finally, `recursive_predicate(-1)`

is false because it does not satisfy the conditions of the recursive rule or the base case.