The more fantastic and irrational the belief system, the more rigid and energetic its defence, it is not the other who disagrees that is being pushed away but rather your own deep seated doubt.

Hidden within even the most liberal mind is a secret fundamentalist desperate for certainty because NOTHING about life is certain.

Indeed, life is the very antithesis of certainty and this scares the hell out of most of us. Instead of imbuing life with a false structure and stability, some brave souls among us learn to embrace change, embrace flow, and embrace spontaneity and creativity.
This is the path to true peace.

It takes grit to explore the mysteries of life...but some in their minds are ready for constant change but why are they still in a rut?

I think the problem of their state comes from not accepting the rut and just being what it is...we want to be out of the rut, to change...but we can't let go of the rut, so our car continues down this road.

The reason we can't get out of the rut is because we give the rut existence by wanting to get out of it. We can't let go of the rut because we are resisting it. It's like either flowing with the stream of life or swimming against the stream. Life is change that is what it is.

But the rut is what we feel when we resist change like putting our hand in a creek and feeling the flow of water against it.
When I resist my own life, I think that feeling of water against my hand is ME, and I don't want to give ME up...so I continue to resist the stream of my own life. Let go....and the rut disappears.

We are all icebergs showing just out tips. If you want to see the iceberg you have to lower the water, which is a metaphor for consciousness.
Above the water consciousness or light, below the water unconscious or darkness; most of our being is below water.
Spiritual path is discovering how to become more conscious and see our iceberg, which melts when it gets in the light of consciousness.

Strange and wondrous that "nothing is certain" goes from being a fear, to being a mantra, to being "the good news".
I don't remember where I read it, but I read it somewhere along the way and it's a great pointer:

'If you want to find a real treasure, find that which, in your confusion, you've hidden from yourself believing it to be able to swallow you whole. Where would you hide such a thing? Where the last place is you you'd ever think would hold such a great thing.'

So, where is the last place you would think eternity...the interminable weight of nothingness could fit?

Not sure if that would qualify as a "koan" but it doesn't really have any answer that would help anyone unless you answer it for yourself with certainty.

Maybe we don't even have to investigate ...just be willing to listen deeply and silently.

In Zen they say you can't nail a peg into the sky. It seems logical that survival would depend on keeping things the way they are, especially if we like the way things are at the moment.

But the first rule of survival is really counterintuitive:
 "Adapt (change) or die."

The conservative mind has a really hard time with this.

ps/smoh