From article:

  (list (typep "漣" 'simple-array)
        (typep "漣" 'string)
        (typep "漣" 'vector)
        (typep "漣" 'array)
        (typep "漣" t))

  -> (T T T T T)
There you go. The type of "漣" is a subtype of string. Since we know that the type is (SIMPLE-ARRAY CHARACTER (1)), it means that this type is a subtype of string. They are therefore related by the supertype-subtype relationship.

The original intent was that `simple-array`, on its own, is not related to `string`. The referenced type hierarchy makes this clearer: https://lispcookbook.github.io/cl-cookbook/strings.html#stri...