 I was a smoker for lots of years, that's why my voice sounds the way it does. No, actually no, it's true, I was a smoker for many years. I quit many times, I've been successful for quite a long time now. So, I find this self a very wonderful sort of thing. However, craving with a cigarette for cigarettes is a challenging thing and people crave all sorts of stuff so I don't think it just has to be cigarettes. You can crave the outdoors, you can crave snow for all I care. Anyway, the point being that, yeah, we need to ski, but so the term that I'm getting at here is spontaneous recovery, right? So, when you put a behavior on extinction, right, the behavior is going to go up, all right, so let's, the first off, let's not do that. Let's think about classically conditioned behavior, all right? Let's see shit, my examples get all confusing. So, let's just talk about extinction, right? So, extinction in general, you break that connection between whatever it is, the reinforcer and the behavior, you break the connection between the CS and the US. When you drive that behavior down to nothing, right, you think the behavior is gone, right? But when it's classically conditioned, all of a sudden that behavior comes back once in a while. That is called spontaneous recovery. Now, to tie this back into the cigarette example, every once in a blue moon, even if it's been years, years since I have smoked, right, I'll be in a particular scenario that makes me go, I want a cigarette right now. That craving is spontaneous recovery. Now, I don't follow up that spontaneous recovery with the reinforcer. I don't deliver the cigarette. So, I have the craving, right, which is okay to experience. And every once in a while, I do something that I used to always do when I was smoking, like show up in a bar, play some pool. I don't do that very often anymore, but I used to. So, now if I show up in a bar and play pool, I would like immediately crave a cigarette. The other one that always gets me, I don't know why is the smell of transmission fluid. Boom! It brings it right back and that craving just jumps right back in. Now, right now, I'm not having any cravings. Even talking about cigarettes, no cravings, but in the right context, a behavior that's been extinguished, craving cigarettes, has been extinguished, that behavior will jump back up. Here's the cool thing about spontaneous recovery though. It never goes back up to the level it was at. If behavior was up to this level, right, whatever that level means, then you extinguish it, then when you come back on spontaneous recovery, it doesn't get all the way up there, right? It gets almost all the way up there. Now, it's going to happen over and over again. Extinguish, come back, extinguish, come back. It's the idea of spontaneous recovery. It spontaneously recovers.