The reason is that brains were not created for us to perform reasoning, they were created to classify things by emotion -- that is, to prepare the body for responses appropriate to recognized external events. It's important to remember that thinking arose after simple memory-prediction-action chains, and that it's built on top of that legacy system. That's why emotion (using the definition I gave above) is critical: tagging things with emotions and replaying those emotions upon recall is the primary substance and function of brains.

You have already said this in the article, and I basically agree with this model. But it doesn't follow that the categories/responses/tags are in any sense simple. They have the structure of their own, the structure as powerful as any piece of imagination. The structure of these "tags" has complexity still beyond the reach of any scientific investigation hitherto entered upon. ;-) And for this reason it's an error to write them off as phlogiston, even if you proceed with describing their properties.