Think of something basic that you know.
 
‘The earth goes around the sun’, for example.
Or the ‘Central Dogma’ that genetic information flows from DNA to RNA to protein.
 
How would you demonstrate these from first principles? Apart from a few astronomers and nucleic acid experts, the only honest answer for most of us is ‘we can’t’. And very few indeed could do this for both.
 
So why do we think we ‘know’ them?
 
Pause for a moment before you read on. Can you remember exactly how you learned each of these and how it felt at the time? And what makes you continue to believe them? This might seem abstract, almost philosophical, but it is fundamental to understanding what we mean when we say we ‘know’ something in science. And understanding this can reduce the anguish we feel when events contradict our existing knowledge.

Mental maps
We all use mental maps to navigate our world. We have a geographic mental map, our memory of places and routes, that helps us get where we need to go. And we have a societal, or behavioural mental map, our personal blueprint of who is who and how to get things done.
 
Geography is objective and mostly constant: things are where they are. Occasionally new routes or buildings appear. These are easily assimilated into our existing map with a few small changes. We don’t lose sleep over them.
 
Our view of people, procedures and society, on the other hand, is subjective and constantly being challenged. Everyone’s experiences are different and every day brings new ones that we must incorporate into our maps to help us predict how best to handle tomorrow. 

Assimilate or accommodate?
As with geography, we assimilate minor changes easily. When we learn who to ask to order a reagent, or some new detail about a protocol, these are not sources of anguish. The map is recognisably the same, just with a minor tweak. 

​But some new experiences are so far-reaching they challenge our fundamental beliefs and upset us. When someone we trusted exploits us, presenting our idea as their own, or gossiping about something we told them in confidence, it shatters our trust in them and may even force us to review our trust in others too. Our first experience of a grant or paper rejection can throw us into turmoil, bedevilled by the question of whether it was us, or the decision process that failed. And each time we experience overwhelm we are forced to stop and question how it happened and what we could change to avoid it.  

Confusion and doubt
These are double hits: not only do we have to deal with the setback itself but it throws us into mental confusion about why we got it so wrong and what else we might be misinterpreting.
 
The mismatch between our beliefs and experience is known as cognitive dissonance. It feels bad, even if we don’t acknowledge it consciously, because it suggests something about our mental map is fundamentally wrong. A minor tweak won’t resolve it this time: it needs completely redrawing to accommodate this new experience. Only then can we decide how to move forward.
 
But does it have to feel bad? What if we can understand and accept the process and see it as a path to growth?