Imagine a neuron, not as part of the neural organization that we call a "brain" but as a stand-alone living thingy, say, in a Petri dish.  What can it possibly have to say about the Cosmos?  What can it possibly know?  

Now, imagine 100 billion of these living thingamajigs in a vat.   Same question.

Now, put them in a boney box, like the one you are currently in... Same question.

What can we know?!  

Perhaps, nothing much.  Perhaps, everything.