I always look at what peole repeat as an indication of where their mind is at. Tony mentioned the car seat several times. A justification? Tony is spiraling down. When you think about it, is he any different than in the first episode. He still murders; he has affairs; he's still angry and aggressive. One thing that I don't remember ever seeing is Tony hitting Carmela. Could something along those lines be the prelude to his denouement?

"Generosity. That was my first mistake."
"Experience must be our only guide; reason may mislead us."
"Instagram is Twitter for people who can't read."