The intellectual slope doesn't get any slipperier than it becomes when discussing existence. After all, who among us can make a legitimate case for the existence of any thing? If you attach your self to the idea that all things are constantly changing, then moment to moment, nothing remains the same. Add to this observation that there is a perceptual/sensory lag, that is, perception differs in time from the actual event [as well as within the sensory realm, what we are seeing and what we are hearing emanate from differing versions of the thing in question [that is, we see it before we hear it, e.g., lightning and thunder...speed of light v. speed of sound]. And although this might not seemingly make a great deal of difference when considering tiny distances, it certainly does when distances become significant. Our ability to make sense out of the world takes a serious hit when we consider something as basic as existence because there are few ways to obscure the truth of it [by adding complexity]. If x does not equal x+dx, where dx is the change in x over time [a moment], then what exactly does existence mean? Whereas existence and time are attached at the hip, it is easy for many to understand the questionable nature of time but much more difficult to dispense with the idea that we do not exist as we believe we do...as one can make a pretty darn good case for the notion that we don't exist at all!
I don't know of anyone who thinks things aren't changing over time. The universe is expanding. Our sun is burning out. Photons keep arriving from objects millions of light years distant. Stars go nova, spewing out newly created elements, light and gravitational waves. Etc., etc. That isn't some threat or obscuration of the truth of how our universe works. We can use physics to study that aspect of our universe - that is, how it changes over time.
The idea that all things change each and every moment must give rise to the question, "Where exactly is it that we exist?"
I have an address in space and time. My home, my family, and everything else is aging, growing, improving, etc., but that is far from being an existential crisis.
The point of me posting this is to challenge people to confront their basic assumptions. Existence is thought to be such a well understood and accepted idea...but it really isn't at all. All things are the same. Once you begin to see that this is the case, then you might begin to question other known assumptions, as well. It is getting beyond what is assumed that opens people's minds to unlimited possibilities. This is why I have always stated that it's more about understanding the fluidity of life than any particular item. Although we must exist within an exoskeleton of morality, laws, and responsibility, becoming enamored with anything in particular only guarantees that you will be left behind [as life keeps moving forward (with or without you)].
You haven't presented anything of substance that questions existence. Plus, the idea that physics and other sciences ignore change is ridiculous. Evolution is the study of change in life forms. Cosmology is the study of change in our universe. These and other studies are focused on change. Studying something in particular is required if one is to advance human knowledge. Humans don't have time to study everything. Human knowledge has extended to the point where progress in any field requires a lifetime of dedication.
