As Chell carried him to their new home, Cornelius nursed a guilty conscience, and reflected that he was very fortunate that all Companion Cubes had failsafes to protect them from the awful death that AIs call "Paradox Trauma Syndrome".

Companion Cubes all had basic functions hardwired into their systems; these include honesty with their human companions and speaking or acting in their human companions' best interests. Of course, the central programmed function for Companion Cubes is free will, as is vital for all true AI, but the inclination to aid their human companions and answer their human companions' questions truthfully are both very strong in all Companion Cubes.

Cornelius, unfortunately, had had to choose between one or the other.

While Chell had been dreaming, parts of her brain that were normally dead had started firing signals, if only a few, to the other parts of her brain; those places that were normally dead, but had become slightly active during sleep, had held Chell's earlier memories. In other words, Chell was experiencing bits and pieces of her former life in the dreams she was having. On the other hand, Cornelius knew that if she found out about that - if she learned that she really had been the adopted daughter of Caroline - she would be devastated, thanks to Her.

So Cornelius had lied. To his human companion.

And that just wasn't right.

It's better for her that she not know, Cornelius repeatedly reminded himself. I'm only protecting her from her past so that she can move on and find a new life. It's for the best, for her sake.

Still, given what he had been designed to do, the "conscience" part of his programming continuously nagged at him, pushing him to tell the truth; the only reason he didn't is that he knew that if he did tell the truth, his conscience would never let him live that down, either.

I'm doing what's best for her, he told himself over and over again. That is the bigger priority over honesty, and it's what I have to do.

Even if I have to suffer my own form of PTS for the rest of my life…