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.