How did Rey know how to do this?

Question

In The Force Awakens movie, shortly after the mind-reading battle between Kylo Ren and Rey while she is captured, in which she is victorious, she uses a mind-trick on a Storm Trooper (James Bond).

How did Rey know that this would work? It seems odd to me that someone who only moments before, had little idea they had any Force-sensitive abilities, would know.

I know Rey has already had a vision, and Maz already told her the Force is calling out to her, but to me she seemed hesitant to accept these facts. She also seemed to be fairly interested any time the Force or Jedi is mentioned, but this might be because the Jedi are told in stories.

Anything canon or in the novelisation?

Answer 1

After realizing that she had some limited ability to enter Ren's mind, she thinks through the situation and decides to see if she can affect the trooper's mind - because what else can she do?

From the novelization:

What had happened?

Shackled and unable to move, Rey lay on the inclined platform in her restraints, pondering the encounter with Kylo Ren. At first there had been the same pain and fear she had felt in the forest on Takodana. It had intensified as he had probed deeper and she had fought to resist. Then— she had resisted. More than that, it was as if her resistance had somehow turned the probing back on him. For a brief instant, she had been in his mind. She could remember clearly his shock, then concern, and finally a retreat. He had pulled away from her, and out of her mind, with a suddenness that bespoke— not fright; something else. Apprehension, she decided. Whatever she had done had thrown him badly off balance. He had withdrawn: no doubt not only to consider what had taken place, but also to decide how to proceed with her. That meant, most likely, he would be back. She would do anything to avoid that.

And that is what she proceeded to do.

If she could push him out of her mind and enter his, what else could she do? What might she be able to do with regard to someone else? Someone less skilled, untrained in the ways of the Force? The single guard posted just inside the front of her cell, for example?

Answer 2

A popular theory you may see going around is that during her mental duel with Kylo Ren,

she learnt how to use the Force after accidentally breaking into Kylo Ren's mind out of sheer desperation to resist him. That short moment spent in his mind was apparently all she needed to glean all the knowledge she needs to use the Force.

However, unless someone can back it up with actual proof from the novelisations, I would disagree with this theory for the sole reason that her foundation is different from his - whenever she is consciously using the Force as opposed to knee-jerk reactions, she is visibly calm and internally at peace, in the same way as the Jedi of old and not at all like one who would be using the dark side instead.

Examples include her attempt at a mind trick, and the second half of her lightsaber duel with Kylo Ren.

Now that we get that out of the way, I would point out a few facts:

• While in Maz Kanata's castle, her first conscious contact with the Force occurred. She wasn't willing nor able to understand and accept what just happened, but by the time she was done with her mental duel with Kylo Ren, she had spent some time in isolated captivity processing everything and came to the conclusion that she is Force-sensitive.
• Since young, she has heard "stories about what happened". Rumours about the Jedi, the Force and the dark side...and surely what they are capable of.
• She also grew up a scavenger. The mentality such a life develops equips her with the skillset to be more inclined towards creativity, improvisation, and taking things apart to understand how they work.

Putting two and two together, I would suggest that, having accepted her Force sensitivity, she started to walk back through her memories and figure out how she did what she did. Then, having heard stories of what the Jedi of old were capable of, she decided to see if she can do one of them - a mind trick to get a stormtrooper to release her.

It failed the first time, but I guess it helps that Maz Kanata had told her a little bit about the Force, enough to set her on the right path, to compose her mind and emotions. And voila, the second attempt works.

Admittedly, a mind trick is rather advanced - even Ahsoka Tano took time as a Padawan to improve her proficiency until it works unfailingly. However, bear in mind that Luke Skywalker was able to vastly improve his mastery of the Force in the six months between Bespin, when he lost his hand to Vader, to Endor, when Vader lost his hand to him.

We don't have an exact timeframe between Rey's capture to Kylo's interrogation to her escape - it could be days or weeks. However, the fact that she can grow leaps and bounds in her innate ability to use the Force should not be seen as something unbelievable and one of the so-called reasons J.J. Abrams ruined TFA - to do so would be to unwisely set a constraint on what is possible with the Force. Rather, it should speak volumes about just how naturally strong Rey is in the Force.

Answer 3

How did Rey know that this would work?

She didn't... but what has she got to lose by trying. She's already been mind-raped (admittedly, while managing to block and even do a probe back herself), and her immediate future doesn't look like it's going be very entertaining for her.

How did Rey know how to do this?

Again - she didn't. But, Rey has already had some exposure to the force, and given her situation would be desperate to try anything. I won't bother repeating Phantom42's quote from the novelization.