Once again, I have my ESFJ 1 to thank for bringing something to my mind. We were discussing some typings of fictional characters on various blogs, and she brought my attention to some frequently mistyped characters, and I remembered this old dilemma: Which is THE imitating function, Si or Se?
Well, one answer is, they both are. Just in different ways.
The other answer would be Se, in this context. Because it's pretty much always the Se kind that people mistake for Si kind. The Si kind might not even get recognized as imitation.
I understand this mistake is easy to make with all the vague function descriptions out there, but it's also pretty easy to correct if you look at the actual individuals of Se and Si types in real life.
I've had friends of both types who are gifted at imitating in their own ways, so I will use them as examples. Obviously the kind of imitation they do will depend on which are their strong learning channels, so I'll compare two of my friends who are both auditive types.
I had an ESFP friend at school who was really good at imitating voices. She could perfectly pretend to be a certain cartoon character, or a comedian, or the president. Everyone would recognize it right away. This is your ”classic” imitation, I'm sure anyone can recognize it.
My ESFJ roommate is also gifted in the same area, but it might not be as obvious at first glance. Her forte is learning languages fast. I think she made me fully realize the difference between Se and Si a few years ago, when she asked me to give her singing lessons and I gave her a few songs to listen and rehearse, so I could make out the basics of her voice material. Then listening to her, I realized she was able to change her singing technique dramatically according to the original singer of the song (without even realizing she was doing it, or knowing anything about singing). But she didn't imitate the voice of the singer, as my ESFP friend would have. She just sort of moved her own voice along exactly the same ”route” as the original singer, if that makes sense.
So in this case, Se imitates the voice itself, the sound, the colour, the texture. It completely becomes what it hears. Si on the other hand, just repeats exactly what the other voice does, but in it's own way, with its own voice.
It makes sense if you think about the functions: Se adapts according to the environment, Si adapts the environment according to itself. Or at least, that's their viewpoint.