Authors:

If we cannot find a way to interpret the utterances and other behaviour of a creature as revealing a set of beliefs largely consistent and true by our standards, we have no reason to count that creature as rational, as having beliefs, or as saying anything.

"Meaning and Understanding". Book by Herman Parret and ‎Jacques Bouveresse, p. 186, "Radical interpretation", 1981.
If we cannot find a way to interpret the utterances and other behaviour of a creature as revealing a set of beliefs largely consistent and true by our standards, we have no reason to count that creature as rational, as