As I peel off the layers of the onion, I find other layers. But of course, the analogy is biased, because I already know there are layers, hence the onion analogy, and there is no discovery, no insight gained, only another tautology.
How do I experience the world? How can I experience something new if I am always using the same sources, the same inputs, my senses? When I read a book, why isn't it the same every time I read it? How can my perceptions change?
Going through depression has opened my eyes to the bias my brain brings to my perceptions. What I see, hear, smell, taste, touch are experienced in my brain primarily as the attachment, the connection, the association I have with previous experiences. And even worse, the attachment seems to be weighted by the emotional attachment I have with previous experiences, as if the emotion associated with the experience somehow facilitated the magnitude of the memory, as if the greater the emotion associated with the experience, the more likely I was to associate the memory when I experienced a similar experience.
I wonder how emotions are able to affect my memories, which affects my biases.