This not true. Or if it is, it leaving us with the intelligence of a rock. Modern neural network theory is fundamentally how the human brain thinks probabilistically. Excepting innate knowledge (DNA), it provides a scientifically consistent explanation of cognitive function.
That said, we still do no have much of a clue how it all works. But "systematic" thinking is not what models of general intelligence are all about.
At least modern ones. Back about 40 years ago, models were, indeed, all about logic. No longer.
I do not even think Science is a systematic thought process...it may 'involve some systematic thought processes' as a tool. It is the art of careful observation.
Tools include using the deductive powers of math, logic, and modelling (computational deduction tools) to systematically investigate the consequences and causes of the observations.
Generally speaking I think you are sort of right in this article but modern computational cognitive neuroscience has moved a long way in the last 50 years.
