There's a part of the brain snuggled beneath the occipital bone called the cerebellum.  Taking up only 10 percent of the brain's total volume, it contains 70-80% of its cells. Just think, of 100 billion cells, it has 70-80 billion of them.

From birth, every movement, every explicit thought in the frontal part of the brain is copied in the cerebellum as an internal model.  The cerebellum collects and inventories them to aid the organism in responding to environmental stimuli implicitly, below the level of conscious awareness.

Childhood internal models, good or bad, become unconscious behavior prompts during adolescence and adulthood.  The child is father of the man.

During problem solving, cerebellum picks relevant internal models, even blending them to aid the frontal working memory to reach a solution, taking the form of insights and intuitions.

I believe cerebellum, ethnically shaded, is the strength of our diversity.  Ten persons from different parts of the globe, reach solutions to problems more quickly than ten persons from a single country such as China, explaining, perhaps, why they are so theft minded of our secrets.

Read Masao Ito, Larry Vandervert, Jeremy Schmahmann, researchers who informed us the cerebellum does for thought what it does for movement.

Hope this helps to explain where, I'd say, most of our thoughts come from.