 I can hardly think that he could have failed to see that. Besides, if you want a textual justification for that kind of thinking, I think we find it in this reference to the dream that you find in verse 8. When his brothers came down there and bowed before him, we're told in verse 8 that although Joseph recognized his brothers, they did not recognize him. And then verse 9, he remembered his dreams about them and said, you are spies.