What exactly is the critical faculty?

In traditional hypnotherapy teaching, the critical faculty describes the process by which we question information before accepting it. If someone makes a suggestion that conflicts with what we believe, we may examine it, reject it or simply dismiss it without much thought.

The term is particularly associated with the hypnotist Dave Elman, who described hypnosis in terms of the critical faculty being “bypassed” and selective thinking becoming established. That historical explanation has influenced generations of hypnosis teaching, including how therapists talk about conscious and unconscious processes.

But the words deserve care. There is no small anatomical gate in the mind labelled critical faculty. Nor do the conscious and unconscious mind exist as two separate physical compartments between which a therapist can open a door. They are ways of describing different aspects of human experience and mental activity.

A more precise modern explanation is that we continuously make sense of the world by combining incoming information with memories, expectations, attention, context and goals. This can happen deliberately, such as when we assess a surprising claim, or rapidly and automatically, such as when we recognise a familiar voice.

So, when we say somebody's critical faculty has “kicked in”, we usually mean that they are evaluating the plausibility or personal relevance of what they have heard. Their response may be thoughtful and well evidenced; sometimes it may simply be habitual.

What is the purpose of the critical faculty?

Imagine having to assess every noise, object, instruction and conversation as if you had never encountered anything similar before. You would never get to the end of a normal morning. Previous learning helps us make quick judgements, and careful evaluation helps us question information that matters.

That last point is often overlooked. A useful critical process does not exist to keep everything out. It helps us decide what deserves a closer look.

How does the mind evaluate a new idea?

For teaching purposes, I like to explain it as four overlapping stages. They are not literal departments of the brain, and they often happen too quickly for us to notice. But they make the process easier to understand.

Back to our talking dog

If you heard a dog bark and somebody said the sound was really a full sentence, you might first think they were joking. That would be a perfectly reasonable starting point. If they then played a convincing recording, you could inspect the recording, ask where it came from and consider other explanations such as editing, mimicry or a toy nearby.

What you would not need to do is believe immediately — or decide that no possible evidence could ever change your view. Being sceptical and being curious are not opposites.

A more everyday example

Perhaps a friend says you handled a difficult presentation very well. If your existing belief is “I'm terrible at speaking in public”, you may dismiss the praise and remember only the moment your voice shook. The praise is new information, but an old belief has influenced how much weight you give it.

That is where our subject becomes interesting for therapy. Sometimes we don't just evaluate claims about the outside world; we also evaluate claims about ourselves.

What does psychology and neuroscience tell us?

Modern research does not identify one single brain centre responsible for all critical judgement. Instead, functions such as attention, working memory, response control, memory and evaluation depend on interacting brain systems and their activity in context.

Expectations shape perception

Our brains do not experience the world as completely blank slates. What we have learned before can influence how we interpret what we see and hear. Researchers study this through ideas such as predictive processing and perceptual inference: the brain combines sensory information with prior expectations. These are active areas of research, not a complete explanation of every thought we have.

This ability is useful. It lets us recognise familiar situations quickly. But it also means our initial interpretation can sometimes be wrong, particularly when the information is ambiguous.

Confirmation bias

Psychologists use the term confirmation bias for a tendency to notice, select or interpret evidence in ways that support what we already believe. This is not proof that people are irrational all the time; it is a well-studied pattern that can influence reasoning, even in people with considerable expertise.

For example, someone who believes “Nothing ever works for me” might notice two disappointments while overlooking several modest improvements. Another person who believes “Everything will be fine” might overlook warning signs. Either interpretation becomes unhelpful if it stops them seeing the fuller picture.

Metacognition: thinking about our thinking

Metacognition is our ability to reflect on our own mental processes. Questions like “Why am I so certain?”, “Am I making an assumption?” and “What else could explain this?” are examples. Metacognition gives us a useful way to pause and reconsider a first reaction.

What happens when the critical faculty seems “too critical”?

In my original article, I asked whether we can become so critical that we fail to recognise information which might be true or useful. I still think that is a worthwhile question, although I would put it slightly differently today.

Rather than saying the critical faculty becomes too powerful, we can ask whether a belief has become too rigid to allow new evidence in. There is a difference between sensible doubt and automatically dismissing every alternative.

It's important not to turn this into another criticism of the client. A protective belief may have developed for understandable reasons. It may once have helped somebody feel safer. The work is not to tell them their belief is silly, but to help them examine whether it remains useful or accurate now.

This is one reason I favour Solution Focused questions. They can invite a person to notice exceptions to the usual story, recognise what is already working and consider what a next step might look like — without insisting that they accept a new belief on command.

Balance: neither gullible nor closed-minded

There is a sensible middle ground. If we accept every idea without question, we become vulnerable to misinformation, unrealistic promises and poor decisions. If we dismiss everything unfamiliar, we may miss learning, opportunities or evidence that an old assumption needs updating.

Notice that balanced thinking does not require us to abandon judgement. In fact, it often asks us to use judgement more carefully.

Does hypnosis really “bypass the critical faculty”?

This is probably the question most students of hypnotherapy want answered. In traditional teaching, the answer is often described very simply: as a person enters hypnosis, the critical faculty is bypassed, making suggestions easier to accept.

It is a memorable description. But as a literal scientific claim, it goes further than the evidence allows.

What we can say with more confidence

Hypnosis involves focused attention and an increased capacity to respond to suggestion. A hypnotic context can help someone become absorbed in an image, possibility or experience. Suggestions can influence aspects of perception, attention, behaviour and the sense of agency in some circumstances. People vary in how strongly they respond.

It does not follow that critical judgement is switched off, that a hypnotist gains control of another person's mind, or that every suggestion is accepted. The Royal College of Psychiatrists specifically explains that people remain in control and do not have to follow suggestions they do not want to follow.

Research reviews continue to debate how suggestions work. Different explanations focus on attention, expectations, metacognition, social context, learning and changes in subjective experience. There is no accepted single “critical faculty switch” that researchers can point to on a brain scan.

What about selective thinking?

In older hypnosis language, selective thinking describes becoming absorbed in an idea or response. That can be a useful description of a person's experience. I would teach it as historical theory and practical metaphor, not proof that one part of the brain has been disconnected from another.

Think about becoming absorbed in a good book. You know the characters are fictional, yet you may feel sadness or excitement as the story unfolds. The analogy helps explain how an imagined experience can feel meaningful while we retain knowledge of what is real. Reading a novel and undergoing hypnosis are not identical processes, but the comparison can make focused imagination easier to understand.

Is a deep trance necessary?

Not necessarily. Responsiveness to suggestions and hypnotic depth are different ideas, and a high score on a laboratory scale does not guarantee a clinical outcome. Equally, a lower score does not automatically mean that therapy will be unhelpful. I explore this in more detail in my guide to hypnotic depth scales.

Why this matters in the therapy room

As a Solution Focused Hypnotherapist, I am more interested in helping the person in front of me identify useful changes than in proving I have somehow overpowered their critical judgement. Good therapy should leave someone with more confidence in their ability to make choices, not less.

During an initial consultation, we might explore what they would like to be different and how they would recognise progress in everyday life. If somebody says, “I never handle pressure well”, I would be interested in occasions when they coped a little better than expected. We might look for the smallest practical difference rather than demanding they adopt a completely new self-belief.

Suggestions should offer possibilities, not override reality

A statement such as “You are completely calm now” can feel unhelpful if the client is clearly anxious. A gentler, accurate invitation might be “I wonder whether there has been even one moment today that felt a little easier?” Equally, there are times when direct, simple instructions are appropriate and reassuring. The wording should fit the individual and the agreed purpose.

That is why I prefer to talk about collaboration, imagination and informed choice rather than making a client believe their protective judgement has disappeared.

What should a therapist avoid?

• Promising that hypnosis will make a person believe something, regardless of their wishes.
• Using leading questions to suggest forgotten memories or to present imagined events as factual.
• Dismissing genuine concerns as “resistance” or evidence of an overactive critical faculty.
• Making assumptions about a client's medical needs, diagnosis or suitability for hypnosis.
• Claiming that the therapist can remove fear, anxiety or habits through suggestion alone in every case.

Where someone has a history of psychosis or schizophrenia, the NHS and Royal College of Psychiatrists advise particular caution about hypnotherapy. Any clinical work should involve appropriate assessment and referral where needed. Informed consent and the client's capacity to decline are fundamental.

Three useful ways to examine an old belief

These are general reflection exercises, not suggestibility tests, diagnoses or substitutes for therapy. They are ways to encourage curiosity while keeping good judgement intact.

Four myths worth clearing up

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