Have you ever noticed that for every positive thought you have, you have 4-5 negative ones at the same time, or right afterwards? It almost seems like your brains want to be negative, doesn’t it?

That’s because it does. In fact all human brains are wired with a bias towards negativity, because that bias helped us survive. Today I’m going to teach you why your brain operates like this, and how you can begin to retrain it to focus more on the positive and less on the negative.

Imagine you’re a primitive human, one of the original homo sapiens. Your environment is filled with dangers—animals that want to eat you, rushing rivers that might carry you away, poisonous plants that look a lot like non-poisonous plants. There’s no written language, no plant encyclopedia you can consult about which berries are safe, no way to Google “how to hide from lions.”

The only way to ever get any safer is to retain information and knowledge about dangers. It’s much more important for you to remember which berries are poisonous than which berries are delicious. If you make a mistake on whether a berry is delicious, you just have a “blah” meal. If you make a mistake on which berry is poisonous, you die. So, if you’re a primitive human who’s good at remembering which berries are delicious, but always forget which are poisonous, you probably died pretty early on.

If, on the other hand, you were one of the primitive humans who was good at remembering which berries were poisonous, you probably survived much longer and passed on your “poison-remembering” genes. You also taught your children what you learned. Over generations, those humans that survived were the ones who were good at remembering which berries were poisonous, where the lions like to hunt, and which rivers had powerful currents.

Our brains have a structure inside them we share with other vertebrate animals, and it’s associated with what scientists call “negative feedback” or “negative rewards.” In other words, this part of your brain is specifically dedicated to remembering things like pain, suffering, injury, or other negative outcomes. It exists to remember all the negative things that have ever happened to you, to keep you worrying about them and looking-out in case they happen again.

However, as humans, we also possess more evolved brain structures that can imagine the future. It would be nice if our brains automatically imagined wonderful outcomes for us all the time, but that’s not how we work. Imagine again you exist in a world full of physical, life-threatening dangers. Now imagine two primitive humans. One of them assumes there’s no danger and that everything is safe and wonderful, so she jumps in rushing rivers, pets lions, and eats anything she finds. The other is constantly imagining what might kill her and acts very cautiously as a result. Which one of these humans is more likely to survive and pass on her genes, as well as teach her offspring her approach?

Ultimately what all this means is that it makes very good evolutionary sense for your brain to have a bias for negativity. But if you’re reading this blog, the odds are you do not live in a physically-dangerous environment. Your daily survival does not come down to distinguishing which berries are poisonous or which animals are going to eat you. In fact, one of the biggest threats to your health and survival now is the chronic stress that your brain creates by interpreting everything around you as a life-or-death emergency and dwelling on the negative. The bias for negativity has become a maladaptation.

Understanding that your brain has a bias for negativity is hugely important, because it gives you a very good reason not to simply believe the negative thoughts your brain throws at you. We all start out simply believing whatever our brain says is true, but the negativity bias means our brains are not reliable narrators. They don’t remember, imagine, or predict the good and the bad equally or objectively. They’re wired to disproportionately remember and predict the negative many times more than the positive.

The next time your brain is going off on a negative tirade, simply remember that it has a bias for the negative. You don’t think all these negative thoughts because they are true, and you also don’t think them because there’s something wrong with you, or your brain is broken.

Everyone who has ever changed their thought processes started with that same negativity bias—you are not a special snowflake! My brain started out the same way, and I changed it over time, on purpose, by practicing the tools I teach you. Every brain starts with a negativity bias, and every brain can be unf*cked anyway.