The essay brings a summation of human efforts seeking to understand our existence.Plato and Kant&cognitive science complete reduction of philosophy to a neural mechanism,evolved along elementary Darwinian principles.Plato in his famous Cave Allegory explains that between reality and our experience of it there exists a great chasm,a metaphysical gap,fully confirmed through particle-wave duality of quantum physics.Kant found that we have two kinds of perception,two senses:By the spatial outer sense we perceive phenomena,objects in space.Our temporal inner sense lets us perceive our inner state,noumena.Kant’s two senses are fully confirmed through bilateral brain duality of cognitive science.The bilateral brain serves inner,temporal sense,logic&noumena in the left hemisphere.The right brain half is for the outer,spatial sense,geometry&phenomena.Weform awhole system,a bilateral interior cosmos,a kind of world model,expressing what may lie beyond the metaphysical gap.In the right brain we build a phenomenal cosmos,to resemble the outer environment.In the brain’s left hemisphere a noumenal cosmos,amodel of our private world including Saint Teresa of Avila’s castillo interior.The cosmos is regularly updated with novel sense data integrated into our memory banks.This was recognized early by Helmholtz(1860s).Our lives,health&well-being depend on us keeping our interior cosmos in good order.This used to be seen as saving one’s precious soul from perdition.While we endeavour to keep our phenomenal cosmos neat&orderly by protecting the environment from harm,our noumenal cosmos to be livable requires us to engage in ethical conduct.This bilateral cosmos is responsible for our common sense judgment power,that we depend on for being able to lead a good&benign life.The 200 million neurons of BA10 in the prefrontal lobe have global access to the interior cosmos,&apply massive feedback to identify environmental conditions rapidly.The global access also gives conscious presence of the individual to itself,all that is presen