Our minds do not view reality directly. We can not process most signals from our environment. Those we do go through a series of electrical and chemical transformations before they reach the brain. There, your mental software has to process it to make sense of it.
There may be light around you, but your brain never sees it. It infers its existence from raw data.
And if it did so faithfully, that would be one thing. But any neuroscientist or psychologist will tell you that we hallucinate our mental models into existing.
When you look at a banana, you do not see a banana. You see splotches of color that match the 'banana' pattern in your mind. Without touching it, you absorb it's soft and sweet. You do not assume it's rigid, scaling or a predator.
The biggest illusion that your brain creates is a tricky one to spot.
It makes you believe that there's a 'you' in your head.
It's like the riddle of sand. A single grain is not a pile. Two grains next to each other do not make a pile. Three do not and four do not … but when you keep adding grains of sand, it ever becomes a pile.
Likewise, a single thought does not make something a mind. Neither do two thoughts, or three.
Have enough thoughts and it sure feels like your sense of self is real.
In both cases, it's an illusion of labeling. Humans find it useful to distinguish a handful of grains and a pile. Reality herself makes no such distinction. The truth is that there are no piles or even grains. It's all a swarm of quarks and leptons that we add labels to.
You can take a pile and swap one grain for another. The pile has not changed. A mind can (and does!) Replace old thoughts with new ones the same way.
“I am my thoughts” is false, given that your thoughts change every day.
Perhaps we are that which changes our thoughts.
Or maybe we're a cloud of sensations that feels like a self.
Once you understand this on a gut level, changing your thoughts becomes easy. Why should a pile care if a grain is removed? How simple is it to add a new one?
This is not about learning to let go of old ideas. It's accepting that there's nothing that could hold onto them in the first place.
If you want an exercise that can help you, I'm happy to oblige:
Earlier today I meditated by focusing on a single sense – in this case, the sound of water trickling along a creek.
I placed all of my attention here.
I thought about how the sound of water exists as vibrations in the air. On another level, the sound only exists in my brain – a reconstruction of electrical impulses from my ears.
The part of my brain that thinks of 'me' as a person relaxed. The separation between 'me' and the environment weakened.
It felt as though the sound were a part of me, as much as I think my hands are.
Then it continued.
I thought of myself as being the sound of the water, while that body over there was part of the environment.
It only lent a moment, but the relief was intense.
People often describe feeling connected to everyone and everything, as if the barbers that separate us come down.
I do not know if that's what what happens.
All I know is it's a healthy and wonderful thing to experience.
When your mind is this open, there's nothing more natural than to leave behind ideas that do not help you anymore.