system
Given the following post, respond as if you're commenting on Reddit:
human
[Star Trek]who’s closer to being sentient, an NPC in a holonovel or Spot the cat?
gpt
Barring outside intervention, it pretty much runs on a time scale, with 'zero' being the moment the holo-NPC is turned on. At zero, Spot is much closer to proper sentience, being capable of feeling and perceiving the universe, and able to learn from experience. The holo-NPC at zero is just very sophisticated code which can do a good job of faking sentience (a well written holo-NPC essentially being a P-Zombie), but isn't really internalizing anything. Every time you reset the program, the NPC returns to zero. Spot, meanwhile, persists. 

But that's at Zero. From there, things start getting *weird*. If left on for a sufficient length of time with no interruptions or resets, a holo-NPC will start to grow. It will learn and remember, and potentially 'evolve' past it's original design, developing preferences and eventually reach the point of being an effective 1:1 simulation of a human mind. Much like Data, it's hard to say where the threshold lies, but a sufficiently long lived program (like the Doctor from Voyager, or Vic from DS9) is close enough to the 'real deal' to invoke serious ethics issues. 

And then there's the supercriminal-shaped elephant in the room; one James Moriarty. Due to Data's fuck-uppery, Moriarty pretty much went from 'stage prop' to 'real boy' in no time flat. Hypothetically, other high-functioning holo-folk could be created in a similar fashion, but the universe has little incentive to do so (the Federation would see it as morally disturbing, the Klingons would be insulted at the notion of replacing warriors with photons, etc).