Several decades ago, I was driving along a country road looking for a cabin owned by a friend of mine. The directions he had given me were vague at best. I came to a spot where the very rustic road vanished completely. I saw an old sign that read:

“STOP! NO MOTOR VEHICLES BEYOND THIS POINT.”

I sort of parked the car, and proceeded to walk along a well-marked foot path a couple of dozen yards to a clearing, where I could see the cabin in the distance.

I had been somewhat annoyed when I started walking, since I had a lot of gear in the car I would need to haul to the cabin, but I soon got over it, and for the week I stayed there, I came to appreciate the total silence and solitude that came with being “off road”.

When it comes to knowledge we have become used to a certain way of moving forward. We have the smooth, well-paved road of science, which many think can go everywhere we might want to visit. We travel down that road on our conveyances of rational induction, objective reproducibility, and other vehicles mass-produced by the Scientific Method Transportation Co. And we almost always get where we want to go, or at least where the road takes us.

But almost always is not always. There are a few roads in our scientific universe that also have STOP signs. Signs that say “Go no further in your vehicle.” In order to continue we need to dismount, and go on foot, or with some other kind of conveyance.

This is not a popular idea among some modern atheists – those who subscribe to a view that many theists call scientism. One definition of scientism could be the belief that such STOP signs do not exist and cannot exist, that everything we ever might want or need to know about anything can be achieved with the scientific method, and only with the scientific method.

I once had a strange conversation with a scientism-believing atheist about how we could possibly evaluate the quality of art using objective, scientific criteria. He informed me that it was easy – in order to get a good quantitative measure of the artistic value of a painting, simply find out its current market price and compare it to the average market value of other paintings. He was serious.

In fact, it isn’t only art, values, and philosophical ideas that resist scientism. Most importantly, science itself proves its falsity. Physics has told us that there are some things we cannot know: there are STOP signs we cannot pass using science. The position of an electron cannot be known at the same time as its momentum, ever, anywhere, by anyone. The Uncertainty Principle is not in place because we need to do more research; it’s the result of research and it won’t change.

Just recently another unexpected STOP sign showed up in physics. A paper in Nature called “Undecidability of the Spectral Gap” proved mathematically that it is sometimes impossible to determine the properties of the energy difference between the ground state and first excited state of a system, which is called the spectral gap. I don’t know nearly enough physics to be able to understand what this means, but I think I understand the basic conclusion of the paper: “Our result implies that there exists no algorithm to determine whether an arbitrary model is gapped or gapless…”

So we now have an undecidability issue, along with an uncertainty principle and Gödel’s incompleteness theorem in mathematics. All of this is strictly within science. None of this is unexpected – scientists have always known that there must be limits to how far they can go in understanding all aspects of reality (see my previous post about constants). Science is often unable to address ‘why’ questions, especially those associated with human emotions and purpose. I think that as we go further in biology we will come across a few STOP signs also. There are some aspects of cellular biology that are starting to look as complex as quantum mechanics.

So the question is, if and when we come to a STOP sign and can go no further in our scientific-rational-materialism vehicles, should we still try to make progress? If we don’t want to give up and say “Well, we can go no further with science, so we’ll just turn around and go home”, then how do we proceed? What kind of vehicle should we find? I don’t know the answer, but I do know there are a lot of options. We can try the bicycle of philosophy, the skateboard of psychology, or sometimes we might want to use the moped of theology. I would say whatever works is worth a try, even if it means striking out on foot, with whatever crazy, personal, brand new idea that nobody has ever thought of in our backpack. We might not get there, but the trip is worth the effort. And who knows what we will find past the STOP sign.