Dr Caroline Leaf – Thoughts are real. So what?

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Today’s meme from Dr Leaf is one of her favourite, often repeated phrases:

“Thoughts are real and occupy mental real estate.”

Dr Caroline Leaf is a communication pathologist and a self-titled cognitive neuroscientist. Her entire preaching empire rests on her assumption that our thinking is the driving force of not just our mental health but also our physical health, and even physical matter!

No one’s denying that thoughts are real. The key issue is not whether thoughts are real, but what thoughts really are.

Professor Bernard J. Baars is an Affiliate Fellow at The Neurosciences Institute in La Jolla, California. He is a real cognitive neuroscientist. In the late 1980’s, Professor Baars built on Baddeley’s model of working memory by proposed the Global Workspace theory [1]. Together with Professor Stan Franklin, also a real cognitive neuroscientist (and a mathematician and computer scientist) at the University of Memphis, they took the Global Workspace theory further with the Intelligent Distribution Agent model [2]. Central to this model is the “Cognitive Cycle”, a nine-step description of the underlying process from perception through to action. In the model, implicit neural information processing is considered to be a continuing stream of cognitive cycles, overlapping so they act in parallel. The conscious broadcast of our thought stream is limited to a single cognitive cycle at any given instant, so while these thought cycles run in in parallel, our awareness of them is in the serial, sometimes disparate, streams of words or pictures in our minds. Baars and Franklin suggests that about ten cycles could be running per second, and since working-memory tasks occur on the order of seconds, several cognitive cycles may be needed for any given working memory task, especially if it has conscious components such as mental rehearsal [2].

In recent years, the Global Workspace/Intelligent Distribution Agent hypothesis has been updated to help facilitate the quest to create different forms of artificial intelligence. The LIDA (“Learning Intelligent Distribution Agent”) model incorporates the Global Workspace theory with the concepts of memory formation to create a single, broad, systems-level model of the mind.

Franklin et al summarise the process, “During each cognitive cycle the LIDA agent first makes sense of its current situation as best as it can by updating its representation of its current situation, both external and internal. By a competitive process, as specified by Global Workspace Theory, it then decides what portion of the represented situation is the most salient, the most in need of attention. Broadcasting this portion, the current contents of consciousness, enables the agent to chose an appropriate action and execute it, completing the cycle.” [3]

Information within the cognitive cycle is broadcast to our consciousness in order to recruit a wider area of the brain to enhance the processing of that information [2, 4]. It’s the broadcasting of this portion of the information flow that renders it “conscious”.

So thought is nothing more than a broadcast of one part of a deeper flow of information. In the same way that a projection on a movie screen is a real series of images of a historical or fictional event, but not the actual event, so thoughts are a real but are just a projection of the deeper information stream within the brain.

This is very important, as it means that thought is not an instigator or a controlling force. It’s not a case of, “I think, therefore, I am”, but, “I am, therefore, I think.

So Dr Leaf is right, thoughts are real. So what? Thoughts are just a projection, a function of the brain. They are not independent of the brain and they do not control the brain. And they definitely don’t control physical matter.

In posting things like todays meme, Dr Leaf is proving just how far her assumptions are from the work of real cognitive neuroscientists, while misdirecting her audience, duping them into believing that her tenuous speculation is scientific fact.


[1]        Baars BJ. A cognitive theory of consciousness. Cambridge England ; New York: Cambridge University Press, 1988.
[2]        Baars BJ, Franklin S. How conscious experience and working memory interact. Trends in cognitive sciences 2003 Apr;7(4):166-72.
[3]        Franklin S, Strain S, McCall R, Baars B. Conceptual Commitments of the LIDA Model of Cognition. Journal of Artificial General Intelligence 2013;4(2):1-22.
[4]        Baars BJ. Global workspace theory of consciousness: toward a cognitive neuroscience of human experience. Progress in brain research 2005;150:45-53.

Dr Caroline Leaf and the Mental Monopoly Myth (Mark II)


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In my last post, I asked the question, “What’s more important to a person’s health and well being?” and I showed that Dr Caroline Leaf proposition that the mind dominates ones mental health and well-being is patently false.

Not to be outdone, Dr Leaf countered today with a tweak to her initial proposition: “Mind-action is actually THE predominant element in mental well-being.”

Dr Caroline Leaf is a communication pathologist and self-titled cognitive neuroscientist. She’s also started calling herself an expert in mental health, despite never having trained in medicine or psychology, or working in counselling.

Dr Leaf may have tightened up her wording from her previous statement, but her claim that mind-action is the predominant element in mental well-being is still wrong, because her fundamental assumption is wrong.

What fundamental assumption? That the brain doesn’t control the mind, but the mind controls the brain.

As I discussed in the last post, this idea of the mental monopoly dominates every one of Dr Leaf’s works, and most of her social media memes. Take her most recent meme for example, published just today, “The brain is not a chemical stew that is missing a key spice! The brain is hugely complicated and complex and is controlled by the even more hugely complex and eternal mind!”

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The premise that the mind controls the brain is wrong. Completely and utterly wrong. It is precisely the opposite of what science tells us. The mind is a function of the brain, just like breathing is a function of the lungs. No lungs, no breath. No brain, no mind. (see my posts here, here and here, and others for further discussion)


It’s been said, “Consistency: It’s only a virtue if you’re not a screwup.” Perhaps that’s a little harsh, but it does illustrate the point that just because you say something often enough, doesn’t make it true. So no matter how many times Dr Leaf repeats herself, the fact that the brain controls the mind isn’t going to change.

Even without appealing to the plethora of scientific information out there, Dr Leaf’s claim that mind-action dominates mental well-being is wrong, since mind-action is simply brain-action, which in turn, is influenced by the complex interplay of our genes, our physical health, our uncontrollable external environment, our social networks and our spirituality. Our mental well-being is no different to our general well-being in this regard. It is still part of the complex interplay that is represented by the biopsychosocial (and spiritual) model.

It’s time for Dr Leaf to update her teaching, and abandon her unscientific presuppositions and philosophies.

Dr Caroline Leaf and the Mental Monopoly Myth

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What’s more important to a person’s health and well being?

Is it their physical attributes – their genes, their fitness, their diet? Is it their psychological state – their mind, their emotional balance? Is it their social context – how they relate and contribute to the communities that they’re a part of? Or is it their spirituality – the depth of their connections to faith and the supernatural?

According to Dr Caroline Leaf, communication pathologist and self-titled cognitive neuroscientist, it’s the mind that dominates. This is a common theme of her books [1: especially chapter 1] and her social media memes.

Take today’s gem: “Mind action is the predominant element in well being and mental health.”

In other words, it doesn’t really matter what your genes are, where you were born or the depth of your acceptance in your community. It doesn’t matter whether you have a deep faith either. The psychological dominates the physical, the social and the spiritual. As she said in her books,

“Thoughts influence every decision, word, action and physical reaction we make.” [2: p13]
“Our mind is designed to control the body, of which the brain is a part, not the other way around. Matter does not control us; we control matter through our thinking and choosing.” [1: p33]
“Research shows that 75 to 98 percent of mental, physical, and behavioural illness comes from ones thought life.” [1: p33]

Dr Leaf’s philosophy of our wellbeing can be pictured like a pyramid, with our ‘mind action’ (read, ‘choices’) dominating every other facet of our lives.

Leaf Mental Monopoly Model

The problem with this philosophy is that it doesn’t fit with science, scripture, or even common sense.

You don’t have to be a rocket scientist to recognise that Dr Leaf’s assertion doesn’t fit with every day experience. Where you were born and raised, and where you live, significantly impact a persons overall wellbeing, independent of their thoughts and choices.

Does Dr Leaf honestly believe that the wellbeing of a ten year old boy living in rural Sedan, with no access to running water and sewerage systems, living on a subsistence diet and drinking contaminated water from the only well in his village, has the same wellbeing as a ten year old in rural Ohio, who has access to clean water, plentiful food, and an education?

Does Dr Leaf think that the wellbeing of a pregnant woman in Afghanistan, with poor nutrition and limited access to meaningful antenatal care or a trained midwife to deliver her baby, is the same as the wellbeing of a pregnant woman in London, who has access to fresh food, vitamin supplements, GP’s, midwives, and specialist obstetricians in big city hospitals?

These are just two simple examples which demonstrate that the action of your mind has very little to do with your overall wellbeing.

But if you want to be more scientific about it, then look no further than the biopsychosocial model. Modern health professionals moved beyond the idea that only one facet of human existence was responsible for all of your wellbeing way back in the 1980’s. The biopsychosocial model proposes that the overall health of a person was equally dependent not just on the physical, but was part of a broader system of the medical, mental and the social [3]. The model recognised that a person’s overall wellbeing was made worse by social disadvantage as well as physical illness or poor coping skills, and so often, the physical, social and psychological would affect each other in loops – physical illness would often reduce a persons ability to mentally cope, which strained their social connections, making them lonely and reduced the care given to them, which then made them sicker.

Most Christian would recognise that one element is still missing, which is the spiritual. Our faith is a realm beyond rational thinking, and isn’t fairly grouped with the mental, although they are both housed in our brain. Still, faith influences our social interactions, our psychology, and our physical health, as much as each mutually influences our faith.

Putting it altogether, we don’t have a pyramid, but a collection of ponds. Our mind action does not dominate our health and our wellbeing, but is simply one part of a much larger whole, with our health and wellbeing at the centre.

Biopsychosocial spiritual coloured

It’s interesting that a woman with as much influence amongst the western Christian church as Dr Leaf would suggest that the mind is more influential to our wellbeing than our faith. This makes her teaching seem more humanist than holy, more secular than spiritual. It may invite questions about the deepest influences of her ministry – is it humanistic philosophy with a garnish of scripture, or does the Bible really promote thinking over faith? Ultimately, it’s up to each individual to examine the evidence for themselves and make up their own mind.

Irrespective of Dr Leaf’s philosophical foundations, I’d suggest that her hypothesis of the mental monopoly falls down at the level of common sense and good science. Medical science moved beyond the idea of the single dominant facet of humanity more than three decades ago.

It’s time for Dr Leaf to do the same.


[1]        Leaf CM. Switch On Your Brain : The Key to Peak Happiness, Thinking, and Health. Grand Rapids, Michigan: Baker Books, 2013.
[2]        Leaf C. Who Switched Off My Brain? Controlling toxic thoughts and emotions. 2nd ed. Southlake, TX, USA: Inprov, Ltd, 2009.
[3]        Borrell-Carrio F, Suchman AL, Epstein RM. The biopsychosocial model 25 years later: principles, practice, and scientific inquiry. Ann Fam Med 2004 Nov-Dec;2(6):576-82.

Dr Caroline Leaf – Better graphics, same content

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In the world of marketing, visual media is king. Humans are sight based creatures. About thirty percent of our brains cortex is dedicated to vision , compared to 8 percent for touch and 2 percent for hearing http://channel.nationalgeographic.com/brain-games/articles/brain-games-watch-this-perception-facts/)

It’s no wonder then that sites like Pinterest and Instagram have so rapidly become such dominant sites on the social media landscape. And why billions of dollars are invested in visual advertising on TV and billboards.

Dr Caroline Leaf is a communication pathologist and self titled cognitive neuroscientist. In the last few weeks, she’s gone for a new look for her Instagram and Facebook posts – gone are the simple lines, plain text and stand alone logo. Her posts have gone glam, with backgrounds of her photo treated with coloured layering and shading, overlaid with Dr Leafs favourite text. Sometimes the text is pretty easy to read. Other times it looks like a 4th grade class got to take turns picking the font and text size for each different word. But hey, it’s edgy, it’s happening, it’s so hot right now.

It’s a real shame that she only chose to update the look and not the actual content of her social media memes. Take today’s offering as an example: “The mind processes. The brain reflects this processing.” (The unsaid conclusion being that, “The mind controls the brain.”)

I’ve written about this meme a few times (here, here, here and here, as a small sample). But let’s relook at it again, since Dr Leaf is unwilling to reconsider the statements lack of validity.

Does the mind really control the brain, or does the brain control the mind? Well, if the mind was separate from the brain and controlled the brain, then the mind would be able to function independently of the brain. And also, if the mind was separate to the brain, then changes to the brain would not influence the function of the mind.

It’s difficult to show that a person has a mind without a brain. You can’t really remove someone’s brain and then put it back again, so not many people are keen to volunteer for that study. But anecdotally, have you ever heard of a person who has woken from a coma having spend all that time in deep thought?

What IS much easier to study, and has been proven over the course of centuries, is the change to our cognitive function when our brain is changed, physically or functionally.

The mind changes when the function of the brain is changed by medications.
The mind changes when the function of the brain is changed by illicit drugs.
The mind changes when the function of the brain is changed by electrical stimulation.
The mind changes then the structure of the brain is changed by tumours or injuries.

In 1848, a man named Phineas Gage was packing gunpowder in some rock when an accidental detonation blasted a foot-long iron rod through the left face and forehead, severely damaging the left frontal lobe of his brain. History records that his personality changed from polite, well mannered, and well spoken to fitful, irreverent, impatient of restraint or advice, obstinate and capricious [1].

Whilst Phineas Gage was is most famous, other brain injuries can also change the way in which someone thinks. For example, lesions of the parietal lobe of the brain changes the way people see their own bodies. Baars writes, “Patients suffering from right parietal neglect can have disturbing alien experiences of their own bodies, especially of the left arm and leg. Such patients sometimes believe that their left leg belongs to someone else (often a relative), and can desperately try to throw it out of bed. Thus, parietal regions seem to shape contextually both the experience of the visual world and of one’s own body.” [2]

Some might argue that the mechanism of injury might be the variable that could change someone’s personality. After all, if an iron rod was blasted through my skull, I might be a little antsy too. But other structural change to the brain, not associated with a sudden traumatic event, can also result in personality changes – it’s well recognised that personality changes can be the first presenting symptom of brain tumours, for example.

Though the brain doesn’t have to be horribly distorted for the mind to change. In the last couple of decades, a tool has been developed called TMS – short for transcranial magnetic stimulation. A magnetic pulse is delivered over a part of the skull, passing through the bone to reach the brain, causing changes to the electrical current running through the nerve cells. Stimulation of different intensities can either turn off the nerve cells or excite them. TMS has become a great tool for studying cognitive neuroscience because it directly changes the function of the brain in a well localised and temporary manner. It’s also easy for scientists to blind the subjects to whether they’re receiving the treatment or a sham treatment, so the results are reliable. Research shows that when the frontal lobes of the brain are changed by the electrical signals, their executive function also changes [3].

Changes to the function of the brain are known to change the function of the mind and have been known to do so for centuries. From religious hallucinogens to Woodstock hippies, drugs of various forms have been used to alter mood, thought, and perceptions of reality. But there’s a drug that’s much more common, that’s known for its ability to alter our brains thinking ability the world over, and even Dr Leaf enjoys it.

Like most people, my morning doesn’t really start until after my first cup of coffee. Sure, I’m functional, but barely. Fifteen minutes after the first short black is in my system, I find that I’m much more alert and my thinking is clearer.

What’s changed? Is it my mind changing the function of my brain, or is it the coffee, specifically the caffeine in it, that’s changing my brain which is in turn is making my mind clearer and sharper? I think the answer is obvious. Caffeine is the most commonly used recreational drug in the history of mankind, and every cup of java (real coffee that is, not the travesty that is decaf) is more proof against Dr Leaf’s dogmatic misrepresentation of basic science.

So, if the mind is changed by alterations to the structure and/or function of our physical brain, it follows that our mind must be a function of our brain. Therefore, the mind does not process, while the brain simply hangs on for the ride. Rather, the brain processes, and our mind reflects this processing.

Dr Leaf can tart up her memes all she likes, but until she changes the content of her memes to match some actual science, it’s all just smoke and mirrors. The truth doesn’t need visual pimping. It is simply the truth.


[1]        Fumagalli M, Priori A. Functional and clinical neuroanatomy of morality. Brain : a journal of neurology 2012 Jul;135(Pt 7):2006-21.
[2]        Baars BJ. Global workspace theory of consciousness: toward a cognitive neuroscience of human experience. Progress in brain research 2005;150:45-53.
[3]        Guse B, Falkai P, Wobrock T. Cognitive effects of high-frequency repetitive transcranial magnetic stimulation: a systematic review. J Neural Transm 2010 Jan;117(1):105-22.

I’ve got a brain, revisited.

Nearly three weeks ago, I published a post on critical thinking in the church. I briefly discussed what critical thinking was, and I posed a number of possible reasons why we didn’t see more critical thinking in the church.

Having thought some more about the issue of critical thinking in the church over the last three weeks, I wanted to devote one more blog post to it – to add some more to the discussion, and round it out a little.

But first, I want to offer an apology to the church. In the last three weeks, I’ve come across research where experts have looked at the issue of critical thinking across our society, and their conclusion is that critical thinking is hard, and is poorly done across the board. The church, therefore, isn’t necessarily worse than the rest of the community at large, so I may have been a little harsh on account of some unrealistic expectations.

Still, I would suggest that if the Christian church is to be salt and light, we shouldn’t rest on our laurels and think it’s ok to be as undiscerning as everyone else. Instead, we should be looking to lead our community, in our love for God, our love for people, and our love of the truth.

In the essay, “Teaching Critical Thinking: Lessons from Cognitive Science” [1], Tim van Gelder outlines a number of lessons from cognitive neuroscience on the nature of critical thinking, how we learn, and why we don’t learn critical thinking. These have important implications for critical thinking in the church.

  1. Critical thinking doesn’t come naturally to us

    “Humans are not naturally critical thinkers; indeed, like ballet, it is a highly contrived activity. Running is natural; nightclub ‘dancing’ is natural enough; but ballet is something people can only do well with many years of painful, expensive, dedicated training. Evolution didn’t intend us to walk on the ends of our toes, and whatever Aristotle (“Man is a rational animal”) might have said, we weren’t designed to be all that critical either. Evolution doesn’t waste effort making things better than they need to be, and homo sapiens evolved to be just logical enough to survive while competitors such as Neanderthals and mastodons died out.”

    Instead of thinking critically, humans tend to be “pattern-seeking, story telling”. Problems occur because we naturally tend to accept the first account that “seems right” and don’t challenge whether that account is actually true. The test of truth for most humans is not intellectual but intuitive.

  2. Practice makes perfect.
    Critical thinking is a higher order cognitive skill. If you don’t practice the skills, you won’t become good at them or eventually master them. So learning the theory of critical thinking won’t make someone better at critical thinking any more than watching a sport on TV will make you better at it. Though if you want to become really good at something, one needs to engage in deliberate practice of the skills of critical thinking on a regular basis, as well as broadly practicing critical thinking.
  3. Transfer.
    Transfer refers to the difficulty in transferring skills applied in one area and applying them broadly. This is an issue across all learning, not just critical thinking. The mind is a cluster of specialised independent capacities, and a skill learnt in one capacity isn’t easily transferred to the rest.
    Of course, if it were impossible to transfer skills across to our broader knowledge, there would be no point in teaching anything.   So it’s not impossible to broaden critical thinking skills, but this skill must also be learned. It’s unlikely to happen on its own.
  4. Practical theory.
    Australian is a nation of coffee drinkers. Even though we consume a lot of God’s wake-up juice, most coffee drinkers don’t know much about the coffee they consume. They have practical coffee knowledge (what they like), but little theoretical knowledge (why they like it). Improving in critical thinking mastery, just like increasing the depth of coffee enjoyment, involves learning a little more theory. Better theoretical knowledge improves your perception of what’s going on, which then improves insight enabling better self-monitoring and correction, as well as enabling better improvement from external coaching. Better understanding of critical thinking comes from better understanding some of the theory of critical thinking.
  5. Belief Preservation
    Sir Francis Bacon said,

    “The mind of man is far from the nature of a clear and equal glass, wherein the beams of things should reflect according to their true incidence; nay, it is rather like an enchanted glass, full of superstition and imposture, if it be not delivered and reduced.”

    Or in other words, the human mind is prone to illusion, distortion and error, both because of innate hardwiring, and social learning. These cognitive beliefs and blind spots are many, and sometimes subtle. In this discussion, belief preservation is important. It is the tendency “to use evidence to preserve our opinions”. Humans seek out evidence which supports what we believe and avoid or ignore evidence which goes against it. We also rate evidence as good or bad depending on whether it supports or conflicts with our beliefs, and we tend to stick with our beliefs even in the face of overwhelming evidence against them, so long as there is a sliver of evidence in support.
    Critical thinking requires us to work against this bias, and doing so feels very unnatural, so while it might be challenging, it’s nevertheless, very important.

  6. Map it out
    The core of critical thinking is argument (the connected series of statements intended to establish a definite proposition, not an angry dispute).  We tend to handle arguments by expressing them in either writing or speaking. But there concept of an argument map in which the statements that make up the premises and the conclusion of the argument are drawn diagrammatically. Critical thinking skills improve faster when taught with argument mapping.

So how do we apply these lessons to critical thinking and the church?

  1. Critical thinking is hard but not impossible.

Critical thinking doesn’t come naturally to most people. Hence, why I apologised earlier in this essay – I was wrong to expect that critical thinking should come naturally to everyone.

But that doesn’t mean that the church should shy away from it either. At the very least, all Christians should be aware of the most fundamental basics of critical thinking – that we naturally tend to believe what’s intuitive, not necessarily what’s right. And, it’s ok to ask questions. No topic should be taboo.

  1. Those who can, should.

We’re all members of Christ’s body (Romans 12:3-8, 1 Corinthians 12:12-31). Some are more gifted in hospitality or leadership – the hands and feet. Some people are intercessors – the heart. So it’s not really a stretch to think that there are some members of the church whose gifts lie in the academic or the intellectual – the “brain”.

So those who want to think about God and their faith on a much deeper level should be encouraged to do so. If there aren’t any already, courses could be developed to teach the interested Christian how interpret Biblical Hebrew and Greek to increase the understanding of scripture. Courses in critical thinking can be added to every Bible college and seminary, and courses in critical thinking can be encouraged or taught by churches, along side courses in ministry and the supernatural.

At the end of my last post, I said that I would do an idiots guide to critical thinking so that we could all have the skills if we wanted them. Actually I don’t need to, since there are very good courses in critical thinking online already: http://philosophy.hku.hk/think/

  1. Be aware of our limitations

Lastly, pastors and leaders should be aware of their own limitations and their potential for cognitive biases.  Our pastors work hard, and do a very good job on the whole.  But they’re not all like Solomon.  Just because something seems right to them, doesn’t mean that it is. Sometimes there will be people who will legitimately question what they say, or a ministry or minister that they’ve endorsed.

Rather than taking this as an affront to their authority, they need to consider that the alternative view might be right. If they’re not in a position to weigh up the evidence for themselves, there’s no reason why they can’t ask for assistance from trusted elders who do have the knowledge.  If Moses can delegate, then so can they.

The same goes for Christian leaders all the way to the highest levels of church leadership. Our church leadership can’t plead ignorance when significant issues are raised. Burying your head in the sand just makes your arse a target.

Critical thinking is an important yet unrecognised major issue for the Christian church. If I have missed anything, or if you would like to further the conversation, I welcome your comments.

Happy thinking everyone.


[1]        van Gelder T. Teaching Critical Thinking: Lessons from Cognitive Science. College Teaching 2005;53(1):41-46.

I’ve got a brain, and I’m not afraid to use it!

I’ve got a brain, and I’m not afraid to use it! – The issue of critical thinking in the Christian church.

Mythbusters … I have watched a lot of Mythbusters.

For the last decade and a half, Adam Savage and Jamie Hyneman have been exposing various memes and myths to some TV-science scrutiny, to see if whether these culturally ingrained factoids have any element of truth. My sons love it, possibly because of their innate curiosity, though I’m sure the shows gratuitous use of guns and explosives helps.

Most of the time, the Mythbusters prove that the myths they test really are just myths like we expected.  Though occasionally, they come up with some really counter-intuitive results, like elephants really are afraid of mice, that bullets can’t penetrate water, and that a bull in a china shop doesn’t necessarily lead to lots of broken china.

What’s consistently good about Mythbusters is that it shows you can learn a lot by being open minded, and that failure is just as much of an opportunity to learn as success is (sometimes more so). It also demonstrates the value of critical thinking.

There are so many things in our lives that we accept just because other people accept them too. That’s partly because of the way we’re biologically wired, and then socially adapted. While this has its advantages, it’s also deleterious too. Sometimes we do things in ways that are actually wasteful, or accept second best because “that’s the way its always been”.

Because it consists of fallible humans, the church is not immune. If anything, the church is more prone to simply accept what we’re told rather than taking a different point of view and considering issues from alternative perspectives. For example, the push for same-sex marriage caught many conservatives and the church by surprise, partly because the church has been unwilling or unable to engage in public discussion on same-sex marriage without it degenerating into disgust and derision. This has left the arguments against same-sex marriage with holes big enough for spelunking, and has made opponents of same-sex marriage look like a laughing stock (https://www.youtube.com/watch?v=G-0u9Ad886M).

What follows is a discussion on critical thinking within the Christian church. I don’t pretend to have all the answers. Actually, I hope that someone will be able to definitively disprove some of my later observations. Right or wrong, I hope to start an open dialogue on the way the church engages with critical thinking, because it’s a discussion that’s long overdue.

So first, just what is critical thinking? “Critical thinking is the ability to think clearly and rationally about what to do or what to believe. It includes the ability to engage in reflective and independent thinking.” (http://philosophy.hku.hk/think/critical/ct.php)

Is critical thinking Biblical? I propose it is. There’s no verse in the Bible that says, “Thou shalt be critical thinkers.” However, Acts 17:11 talked about those in Berea who searched the Scriptures daily, to see if what they were hearing was true to God’s Word. John and Peter both warned of false teachers, and Jesus said they may come to us in sheep’s clothing (Matthew 7:15; 1 John 4:1; 2 Peter 2:1). John said our duty is to “test the spirits.” Paul said: “Test everything. Hold on to the good.” (1 Thessalonians 5:21).

Is critical thinking being too self-reliant or denying the role of faith? I don’t think so. We don’t expect God to miraculously make us float around from place to place … we walk. God gave us legs, and using them does not deny our faith or God’s sovereignty. In fact, we’d look pretty silly if we sat still and prayed for God to move us around. It’s no different with our brain. God gave us a brain with the capacity for high-level thinking. Using our brain for high-level thinking doesn’t deny either faith or God their rightful place. The Holy Spirit guides us into all truth (John 16:13) and he will guide our thinking if we have the faith to believe.

Is critical thinking necessarily critical? “Critical thinking should not be confused with being argumentative or being critical of other people. Although critical thinking skills can be used in exposing fallacies and bad reasoning, critical thinking can also play an important role in cooperative reasoning and constructive tasks.” (http://philosophy.hku.hk/think/critical/ct.php)

So why don’t we engage in more critical thinking within the church? This is a simple question that requires a complex answer. I’m going to venture a few suggestions, but this list is far from comprehensive, and is more opinion than solid fact. If you disagree, or want to fill in some gaps, please leave a comment to add to the discussion.

1. People in general don’t have critical thinking skills

Critical thinking skills are sadly lacking, not just in the church, but across our society as a whole. Look no further than at the sheer volume of factoids and memes that go viral on social media. The average person accepts large numbers of baseless statements and passes them on to their friends in the mistaken belief that they hold some basis in truth.

There are probably lots of reasons for this, but I’d suggest that the main reason is that critical thinking is not taught in most schools, vocational training, or even at a lot of universities. Teaching critical thinking skills takes time away from teaching exam strategy, which is counter-productive for schools NAPLAN ranking. Since the world cares more about comparing themselves with others rather than actual intelligence, NAPLAN coaching is much more important than letting a child think for themselves.

Most work places actively discourage individual thinking too. Subservience to the system or to organizational rules makes for a much better workplace even if that means it’s full of mindless drones.

2. Christians don’t use critical thinking

The typical Sunday sermon, if it contains any scripture at all, is spoon-fed to the congregation without additional thinking required. It’s obviously difficult to have time for Q+A after a Sunday service, and for the vast majority of Christians, this is where their teaching for the week finishes.

There’s a small percentage of Christians that will go to small groups, but depending on the leadership of the small group, there may not be much opportunity to delve deeply into the text or subtext of the previous weeks sermon.

Then there’s a smaller number of Christians who have a habit of a daily devotional, though many of those will choose to be spoon-fed with a devotional text of some form.

Those who simply read the Bible think critically about the text and what it means will be a very small percentage of the Christian church.

3. Pastors don’t encourage critical thinking

When was the last time a you were at a church and the topic of the sermon was how to delve deeper into the Bible – how to understand the original Hebrew or Greek to enrich the meaning of the Biblical text? I’ve been in churches for more than 30 years, and I don’t recall a single sermon like that.

Perhaps it’s because pastors don’t think people would be able to understand. Or, perhaps it’s because they feel it would erode their position as experts? Perhaps they don’t understand themselves?

4. The church values the appearance of unity over critical thinking

In church-life, a high value is given to the concept of ‘unity’.   Discouraging critical thinking helps to maintain the appearance of ‘unity’. If someone did happen to have a thought of their own, they would tend to keep it to themselves since everyone seems happy when everyone’s in agreement.

When someone does speak out, it’s seen as ‘disunity’, even if their concern is legitimate. Continued non-conformity is treated as dissension. Sure, it’s couched in a thick layer of Christianese – that person’s taken offense / isolating themselves / is a troublemaker / out of God’s will / unteachable / unfaithful / has a critical spirit, etc

While that might very well be true, sadly, any non-conformity is treated the same, warranted or not. Either way, legitimate discussion is shut down, and homeostasis returns.

The solution is to use our brains. The church needs to openly accept and engage critical thinking rather than encourage diminutive homogeny and pretend they have unity.

Just because Jesus is our shepherd doesn’t mean that we should always behave like sheep, just mindlessly following the rest of the flock. God gave us a brain, we should not be afraid to use it.


Post-script = In an upcoming blog, I’ll do an idiots guide to critical thinking. It’s all very well and good to say we should think critically, but that won’t happen if we don’t have the skills.

“Touching the hem of her garment” – A Review of Dr Caroline Leaf at Nexus Church, Brisbane, 2nd August 2015

Dr Caroline Leaf is a communication pathologist and a self-titled cognitive neuroscientist. She’s currently on tour through Queensland and New South Wales in Australia. Her only stop in Brisbane, my home town, was at Nexus, my former home church. Dr Leaf presented a keynote address at Nexus’s annual Designing Women conference yesterday, and was the guest speaker at their two morning services today.

This morning typified Brisbane winter – cloudless azure skies and a refreshingly cool breeze. In contrast to the air temperature, the hospitality at Nexus was warm and friendly. The worship, soulful and uplifting. I really enjoyed being there.

Then it was Dr Leaf’s turn. It’s amazing just how much misinformation one person can fit into a 30 minute sermon.

The main theme for her sermons was an exposition on the parable of the sower, linking the different ways people receive information, with the story of the woman with the issue of blood. Dr Leaf tried to prove that thought and faith are synonymous by linking verses at the beginning and of the story from the gospel of Mark (5:25-34) – “because she thought, ‘If I just touch his clothes, I will be healed.’” (v28) and “He said to her, ‘Daughter, your faith has healed you. Go in peace and be freed from your suffering.’” (v34).

The link is highly tenuous to start with. Faith is an action, whereas thought is not. We assume that action is always preceded by thought, but it is not. Action does not require thought. Many people act without thinking. This is explained in more detail in my discussion on the Cognitive Action Pathways model.

Though to try and make her explanation more plausible, Dr Leaf padded out the story by telling the Nexus crowds that it was only because the woman had spent 12 years in deep intellectual thinking, meditating on the scriptures, that Jesus could heal her. But that’s Dr Leaf’s conjecture. In truth, no one knows exactly what that woman was doing or thinking in the 12 years that preceded her healing. The Bible never says anything else about the woman, in either version of the story in Mark or Luke (8:43-48), other than “She had suffered a great deal under the care of many doctors and had spent all she had, yet instead of getting better she grew worse” (Mark 5:26). If you have to rely on pure speculation to make your sermon work, then that’s story-telling, not preaching.

The other part of her sermon was an attempt to link the parable of the sower to some neuroscience, specifically the role of hippocampal synaptogenesis in the formation of long term memory (or in English, the changes that take place to nerves in the brain when you hear information and try to remember it).

Dr Leaf interpreted the parable as describing four different types of listener – Listener 1, corresponding to the man who hears the word but the devil takes it away, Listener 2, who hears the word and receives it with joy, but it doesn’t take root, Listener 3 who hears the word but it gets choked out by worries, riches or pleasure, and Listener 4 who hears the word and retains it, and the word produces a harvest.

According to Dr Leaf, these types of listener correspond to different levels of nerve branch growth in the formation of long term memory – Listener 1 doesn’t get past 24 hours before the memory dissipates. Listener 2 only lasts about four to seven days but there isn’t enough emotional salience to continue the growth of the nerve branch. Listener 3 doesn’t get past fourteen days, while the 4th Listener makes it through to a full 21 days, Dr Leaf’s magic number for long term memory.

Sounds great … except that the encoding and consolidation of incoming information is much more complex, and doesn’t rely on just new nerve growth [1]. That, and her numbers are completely arbitrary – with some permanent long term memory encoded in a couple of days. In fact, some long-term memory doesn’t need new synaptic growth at all, just a state of high excitation of the nerve network, known as Long-Term Potentiation, which is reliant on a self-reinforcing chemical cascade (if you want more information on the neurobiology of memory, a good place to start is The Brain From Top To Bottom, maintained by McGill University in Canada).

So the bulk of her sermon was based on biblical conjecture and bad science. Dr Leaf also made a myriad of misleading or mistaken statements: we are wired for love not fear, we learn through the quantum zeno effect, every thought effects every one of our 75 trillion cells, your toxic thoughts poison other people in relationship with you because of quantum physics, and many, many others.

I’ve only really got room for a few extra-special mentions.

1. “The mind controls brain”, and “the non-conscious mind is not bound by time and space”

No actual cognitive neuroscientist would be caught dead making those sort of statements. Saying that the mind controls the brain is like saying that air controls your lungs. The mind is a function of the brain, because when the brain is changed in certain ways, structurally or chemically, the mind changes. This has been known about for over a century, at least as far back as Freud who experimented with cocaine and other “mind-altering” substances.

Therefore if the brain controls the mind, then the non-conscious mind must be bound by the physical universe, which includes space and time. To suggest anything otherwise is just science fiction.

Besides, Dr Leaf herself tells us in her book “The Gift In You” [2], that our brain controls our mind. Dr Leaf is simply contradicting her own teaching.

2. “75 to 98% of all physical, mental and emotional illness is caused by your thought life.”

This factoid has been thoroughly debunked. If you would like to read more, you can click here or see chapter 10 in my book [3].

Today, in the second service, Dr Leaf took her fiction a step further and categorically stated that “98% of cancer comes your thought life”. What nonsense! There is no rational evidence for such a ridiculous statement, and I don’t think there is anything more insensitive to cancer victims and their families than to blame then for causing their own cancer.

3. Mental Health

(a) “Mental illness is worse in the last 50 years than ever before”

To try and prove this is true, Dr Leaf flashed up a slide of ‘horrifying statistics” on mental illness. She claims that,
“35-fold increase in mental illness in children”
“Our children are the first in human history to grow up under the shadow of ‘mental illness'”
“Dramatic increase in the number of mentally ill since 50’s … things are worse not better”
“Mental ill health worst its ever been in history of mankind”

Every one of these statements is patently false. Mental illness has been with humankind for ever. The ancient Egyptians were writing about hysteria in women some two thousand years before Christ [4]. It’s only been in the last century or so that mental illnesses have become seen for the biological entities that they are, and not some form of demon possession, criminal behaviour or sexual deviancy.

Dr Leaf was quick to malign the DSM (the Diagnostic and Statistical Manual of psychiatry), suggesting that it’s unscientific. The DSM isn’t perfect, true, but before the DSM, there was even less science to the diagnosis of mental illness. As Dr Leaf herself pointed out, mental illness was previously viewed philosophically or spiritually. There was no consistency in diagnosis and no collection of statistics.

The DSM, for all its faults, gave a framework for mental health diagnosis, but as the science has become more refined, and with increasing awareness and general acceptance of mental health conditions, more people have qualified and/or accepted a diagnosis.

Mental illness has always been there, but now we know what to look for, it’s no longer hidden or ignored.

(b) “Psychotropic medications cause damage to the brain”

While on the subject of mental health, Dr Leaf made the litigation-attracting statement that psychotropic medications (anti-depressants, anti-psychotics) cause damage to the brain. That’s a particularly bold statement to make without citations, or a medical degree, to back it up.

Rather than ‘causing’ damage to the brain, there is scientific evidence that psychotropic medications increase synaptogenesis (the growth of new nerve branches) [5-7], while the NICE guidelines in the UK reviewed the evidence for anti-depressants and found them to be an effective treatment for depression [8], not harmful as Dr Leaf suggests.

(c) Biological causes for psychiatric illnesses have not been proven.

Dr Leaf also made the preposterous claim that biological causes of psychiatric illness have never been proven, but again, changes to brain structure have been associated with psychiatric symptoms ever since a 13-pound, three-and-a-half foot iron rod went through Phineas Gage’s skull and frontal lobe in 1848, and his personality suddenly changed from pleasant and congenial to depressed and angry [9]. Personality changes represent early symptoms of brain tumours. Use of drugs such as crystal meth can cause paranoia and extreme aggression. You don’t even need to be a doctor to know that, you just need to watch ‘Breaking Bad‘. So examples of the biological basis of psychiatric symptoms are everywhere. There are no grounds for Dr Leaf’s assertion.

4. Toxic thinking causes dementia

Dr Leaf claimed at the end of both sermons that toxic thinking results in the tubular backbone of the new nerve branches becoming contorted, which caused the accumulation of the tau protein in the nerve cells, which was responsible for dementia of every type. This, too, is a fallacy. The accumulation of the tau protein is found only in Alzheimers, not in Lewy Body dementia or in vascular dementia. The abnormal tau protein is likely related to the loss of a intracellular clean-up enzyme system [10], but Alzheimers is more complicated than just tau protein deposition, and has nothing to do with toxic thinking.

At the conclusion of the second service, I was outside the church when Dr Leaf and her entourage left the church auditorium before the rest of the crowd did, and I approached them to shake her hand and introduce myself. It was the mature thing to do after all. When I was about two metres from her presidential detail, a woman stepped out in front of me, blocking my way.

“You can’t follow them,” she said. “They’re going inside” (ie: hiding in the green room).
“Really?” I said, somewhat caught off guard. “I was simply going to introduce myself.”
“No”, was the firm reply. “You’re not allowed.”

By that time, the presidential detail had disappeared into their fortified sanctuary. The woman with the issue of blood may have got to Jesus, but there was no way I was even getting close to Dr Leaf.

This was a common pattern … Dr Leaf made herself deliberately scarce before and after each service, only coming into the church when the service was well underway, and leaving as soon as she preached, under heavy guard. One has to ask why? What’s she got to be afraid of? Is she so insecure about her teaching that she couldn’t possibly risk speaking to someone and being exposed as intellectually brittle? Or is it that she’s so arrogant as to insist on avoiding the rank-and-file church goer?

The pattern of avoidance of anyone other than her devotees, and her tendency to block anyone who disagrees with her from her social media accounts, would strongly suggest the former, although since she is so insistent on hiding from regular people, it’s really anyone’s guess.

Not that it matters. Dr Leaf could be the nicest person in the world.  Her ministry doesn’t rest on her sociability, but its own Biblical and scientific merits, and on that alone, it has been found seriously wanting.


[1]        Citri A, Malenka RC. Synaptic plasticity: multiple forms, functions, and mechanisms. Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology 2008 Jan;33(1):18-41.
[2]        Leaf CM. The gift in you – discover new life through gifts hidden in your mind. Texas, USA: Inprov, Inc, 2009.
[3]        Pitt CE. Hold That Thought: Reappraising the work of Dr Caroline Leaf. 1st ed. Brisbane, Australia: Pitt Medical Trust, 2014.
[4]        Tasca C, Rapetti M, Carta MG, Fadda B. Women and hysteria in the history of mental health. Clinical practice and epidemiology in mental health : CP & EMH 2012;8:110-9.
[5]        Karatsoreos IN, McEwen BS. Resilience and vulnerability: a neurobiological perspective. F1000prime reports 2013;5:13.
[6]        Duric V, Duman RS. Depression and treatment response: dynamic interplay of signaling pathways and altered neural processes. Cellular and molecular life sciences : CMLS 2013 Jan;70(1):39-53.
[7]        Karatsoreos IN, McEwen BS. Psychobiological allostasis: resistance, resilience and vulnerability. Trends in cognitive sciences 2011 Dec;15(12):576-84.
[8]        Anderson I. Depression. The Treatment and Management of Depression in Adults (Update). NICE clinical guideline 90.2009. London: The British Psychological Society and The Royal College of Psychiatrists, 2010.
[9]        Kihlstrom JF. Social neuroscience: The footprints of Phineas Gage. Social Cognition 2010;28:757-82.
[10]      Tai HC, Serrano-Pozo A, Hashimoto T, Frosch MP, Spires-Jones TL, Hyman BT. The synaptic accumulation of hyperphosphorylated tau oligomers in Alzheimer disease is associated with dysfunction of the ubiquitin-proteasome system. The American journal of pathology 2012 Oct;181(4):1426-35.