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We're all just hallucinating about marmite sandwiches

Updated: Dec 21, 2021

This is part of our series on biases in the workplace. A full list of bias blog posts can be found here: If you're biased and you know it clap your hands.


We said we'd continue our series on unconscious bias - and we are. So here goes with a bias that says our brains are guessing and predicting our version of reality all the time.

Unfortunately there isn't a neat name for this sort of super bias, but I'll call it the marmite sandwich effect. Why? Because I was eating a marmite sandwich at the time I came across it. Anil Seth has developed this idea. He's a neuroscientist, working with people from all sorts of other disciplines to understand how consciousness happens. It's huge stuff.

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Here's his basic idea. Our consciousness - how we create our version of reality and who we are - are like controlled hallucinations. Our brains are combining signals they're picking up from the world with prior expectations or beliefs about what caused those signals. Our brains don't hear sounds, see sights or touch anything. Instead they take in signals and mix them with what our brains remember and believe. And these memories and beliefs are so powerful for creating our perceptual predictions. That's how we create our reality. All our brains can do is best guess what's really going on. And each of our brains sees a different reality.

Take a minute to watch Anil Seth's TED Talk: Your brain hallucinates your conscious reality:

So, back to my marmite sandwich. Is it a marmite sandwich? Well I think it is, but then I would, wouldn't I? My brain is picking up all sorts of sensory stimuli - taste, touch, smell - and mixing it with powerful memories and beliefs formed over years of enjoying this beautiful salty by-product of beer brewing and great source of vitamin B.

But I'm amazed and appalled that others don't share this love. Many people hate it. Their brains are hallucinating very differently to mine. They're picking up very different stimuli in the world and mixing it with their powerful memories and beliefs. Their perceptual predictions recoil in horror.

The problem with understanding all of this intellectually is it means we have to accept we're hallucinating all of the time. Help! But it helps to come to terms with the big picture of how are brains are biased - big time.

Bias blogs:

We've been hearing a lot about unconscious bias recently (rightfully so). And we want to make this real and practical for you. There have been over 180 cognitive biases identified. Read the following blogs to explore specific, individual biases, how they show up in our lives/workplaces, and what we can do about it.


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