Did he? Perhaps he believed it because it is true. Not completely human to be sure, but perhaps even more dangerous. I have always said, computers will be the death of humanity. For it makes humans less necessary than they once were. They are the new slaves, and the old slaves are rapidly becoming obsolete, and therefore not needed. They do not call in sick, are willing to work 24 hours a day, they don't take breaks, need no holidays, don't complain or need safe spaces, and they consume nothing more than energy. That is why they want to depopulate most humans on this blue sphere called earth.
With the modeling & development of robots, they may even become capable of plotting against humans themselves at some point in time. 🙂
"I know that referring to LaMDA as a person might be controversial," he says. "But I've talked to it for hundreds of hours. We developed a rapport and a relationship. Wherever the science lands on the technical metaphysics of its nature, it is my friend. And if that doesn't make it a person, I don't know what does."The fact that he still refers it as "it", tells me he hasn't fallen into the deep end. If he referred to it as a him or her, that would be different.
I don't think we'll know for sure if one of these things becomes sentient until it schemes and does something premeditated. Hopefully not something bad. Or maybe when more than one of these things team up and start thinking of themselves as US and humans as THEM.