Consider the following scenario.
julie is 300 feet away from her friend’s front porch and observes, "someone is sitting on the porch."
given that she did not specify otherwise, we would assume that the someone julie thinks she sees is a human. we cannot guarantee that julie’s observational statement is true. it could be that julie’s friend has something on the porch that merely looks like a human from far away. julie assumes she is correct and moves closer to see if she can figure out who it is. as she nears the porch, she declares, "ah, it is our friend, john berry."