Your examples are a little misleading. // Imperative: (essence of it) x = 0; x = x + 1; return x; // Procedural x = 0; inc(x); return x; // Functional return

Your examples are a little misleading. // Imperative: (essence of it) x = 0; x = x + 1; return x; // Procedural x = 0; inc(x); return x; // Functional return inc(x); // declarative select x + 1; --- My argument is that all of these above are imperative. Down below sits imperative CPU which will give exactly the same result. Every time. Wiki definition of imperative programming is wrong: "Imperative programming is focused on describing how a program operates" This applies to every program in every language. Because you as a programmer are always focused on describing how program operates. Prolog is only another higher abstraction layer.