The systems could be continuously outputting erroneous data. When mismatch between reality and data output is detected it is inevitably by the unsolicited action of users or customers, in other words, by accident. It never seems to occur to methodologists that there might be a plethora of undetected errors in their systems. Although executable scientific programs, such as the one above, are possible the building of scientific information systems present a considerable challenge. The grammar of natural languages gives no indication of the difference between logically true and factually true statements.
Most people are unconscious of the difference.
Also the logical status of a statement can be regarded differently by different people and at different times. But for the ancient Greeks any man-like being that was immortal was a god not a man. Knowledge based systems with learning capability qualify as scientific information systems. However, most of these, such as medical diagnostic systems, are built within the framework of long established disciplines. Such disciplines have a rigorously defined terminology.