Bishop Berkeley, may I introduce Agent 97.

We were hanging around in the living room yesterday evening when Agent 97, lying on the couch, speculated,"If I can't see something, I can't prove it exists. Like if you're sitting on that chair and I can't see you from here, I can't prove you exist."

Roused to suspicion, I immediately interrogated him as to the source of his idea. "Did you read it somewhere? Did you hear it from someone? Did you learn it at school?"

"No, I've just been thinking about it."

I leaned forward, ready to trap him in an admission. "For how long? Why'd you start thinking about it?"

"For a while. I don't know, I just did."

But what if he didn't see me but he heard me, I queried.

Well, any of the senses, he readily agreed.

I tousled his hair for having independently invented a major philosophical theory, and told him to brush his teeth before bed.