Friends, is Theravada Realist? If so, in what form?
To start with, here's a definition from our friends at Wikipedia...
Realism, Realist or Realistic are terms that describe any manifestation of philosophical realism, the belief that reality exists independently of observers, whether in philosophy itself or in the applied arts and sciences. In this broad sense it is frequently contrasted with Idealism.
Contemporary philosophical realism is the belief that our reality, or some aspect of it, is ontologically independent of our conceptual schemes, linguistic practices, beliefs, etc. Realism may be spoken of with respect to other minds, the past, the future, universals, mathematical entities (such as natural numbers), moral categories, the material world, or even thought. Realism can also be promoted in an unqualified sense, in which case it asserts the mind-independent existence of a visible world, as opposed to idealism, skepticism and solipsism. Philosophers who profess realism also typically believe that truth consists in a belief's correspondence to reality.
Realists tend to believe that whatever we believe now is only an approximation of reality and that every new observation brings us closer to understanding reality. In its Kantian sense, realism is contrasted with idealism. In a contemporary sense, realism is contrasted with anti-realism, primarily in the philosophy of science