Model of Iceland's south coast with inset of aerial view.

Comparator Hypothesis

"The comparator predicts the next likely state of the world, as this will be detected by the brain’s sensory systems...and it compares this prediction to the actual state of the sensory world. All this is done unconsciously. What enters consciousness then consists of the results of the comparison."

Jeffrey Gray (2004)

This is a model of the Icelandic Breithamerkur Glacier, it can tell you much about that glacier, yet in nearly every way it is very different from the land it represents. It seems likely that consciousness works in a similar way. We seem to live in a world when actually we operate within a model, one built for us by our brains from the sensations which are interpreted by perception. This model is good enough for evolutionary success, for success is all that is required of it. Gray writes about how this model might arise out of brain processes, how it depends on feedback mechanisms, and how it forms what we call consciousness. However, care is required, much here is metaphor, and metaphors are slippery beasts at best.


The picture is of part of the model of Iceland in Reykjavik City Hall. The inset was taken from the plane as it arrives over the south coast of the country and shows the glacier at the left of the main image, flowing into the sea. Jeffrey Gray is a neuropsychologist and his book ‘Consciousness: creeping up on the hard problem’ (Oxford Press) offers a systematic, philosophically alert, and uniquely thoughtful account of what consciousness might be. The quote is from p. 312.


Saturday 7th September 2019

Murphy on duty

Details of the
Greeting Card

Go to the contents for this section     Go to the 'Home' page for this site -     Return to the top