lxr asks in a comment to my last post:
Do you have any thoughts on issues of consent with regards to hypnoplay?
After a certain point in trance, I can't imagine how one could even think to safeword.
Before a trance has commenced, consent in hypnosis is just like in other kinds of activities that involve mind-altering states, such as subspace, inebriation, or an adrenalin rush. You negotiate (or not) and agree (or not) to the things you're about to do together. The chances of your hypnotist nefariously taking advantage of you is about the same as your rope rigger nefariously taking advantage of you; you should check your partners out, negotiate clearly, set expectations, etc.
Consent during trance is a different thing, though. Different theorists have different takes on what's actually happening during hypnosis, but I like to think of us as having a conscious and subconscious mind. The conscious mind is your personal narrative mind; it's the thing you're thinking with when you think thoughts that you're aware of. The subconscious mind is everything else, and is most of what's going on in your brain at any given moment.
Normally when we're talking about giving consent, we're talking about an activity of the conscious mind. When you negotiate in advance, you're talking and thinking and agreeing. If you're tied to a table and safeword, it's usually a choice; it's not automatic. You have to decide to say the word.*
The subconscious mind is capable of consent as well. And it doesn't always agree with what the conscious mind thinks about things. For instance, a person's subconscious mind might really want to have sex with that hottie over there, while the conscious mind remembers "oh wait, I'm married." Or the conscious mind might think "a person like me should want anal sex" but the subconscious mind thinks "no way." In day-to-day life, this can look like a person who regrets doing something or who seems confused about what they want.
During a hypnotic trance, the hypnotist is speaking to their subject's subconscious mind. Suggestions can do impressive and amazing things because the subconscious mind encompasses so much of our selves and our personalities, but ultimately, they're just words someone says to you. The subject is the one who has to implement the suggestions. Nothing will happen, hypnotically, that the subconscious mind does not allow.
So at a certain level, hypnotic trance and hypnotic suggestions cannot happen without the subject's consent, making questions of safewords entirely irrelevant.
No problem, right?
Well... no. My subconscious might allow some things that the conscious me wouldn't.**
Fortunately, most subjects during trance have a conscious awareness of what's happening, that I call the observer. It's like the conscious mind has stepped to the side but is still watching everything going on. I have rarely entirely lost my observer, although occasionally my observer has been distracted. Usually, though, my observer is engaged in the trance, noticing stuff, sometimes helping out.
The observer knows what the conscious mind would consent to, and can interrupt. The observer can safeword, or break the trance. To me, this is approximately as difficult as safewording during any other BDSM scene. Other subjects' mileage may vary, depending to a large extent on what they believe about hypnosis.
The hypnotist can make it much easier for their subject by asking them to communicate during the trance, by checking in, by inviting them to safeword. If you use the color system and include green, you can reduce some of the common anxieties around safewording.
The best solution I've seen is for the hypnotist to just give a safeword suggestion to their subject. If a hypnotist instructs their subject to safeword easily, naturally, automatically whenever it's appropriate, even in trance, and refreshes the suggestion periodically, then you're all set. The subject can safeword when they consciously need to, and they will automatically safeword when they subconsciously need to.
I have four automatic safewords: red, yellow, green, and ow. The ow is for when something is causing me physical discomfort that I believe my partner did not intend, but I'm in a state when I could not otherwise communicate it. I have used them in trance without any difficulty.
Negotiation and communication are better tools for establishing and maintaining consent than safewords and always will be. But you can certainly safeword during hypnotic trance, if you believe you can.
* This is part of why safewords are problematic; a lot of players, when they're having things done to them, don't have very much of their conscious mind on-line at the moment. Remembering and forming the intent and saying the word is sometimes not possible. This doesn't mean safewords are useless, as some will contend, but it does mean you can't rely on them in all cases.
** Annoyingly, my subconscious won't allow some things I really want it to. I want my partner to be able to give me hallucinations! Except apparently, deep down, I don't.