The re-evaluation of what constitutes “a thing”, or whether “things” as we think of them even exist. Certainly it’s easy to define objects in our macroscopic world — we can call a set of visible parameters “a person” or ” a planet”. But it seems that “things” are vastly more blurry, the smaller the reference scale — the closer you get to the basics of life’s constituents.
If “things” don’t quite hold up, then neither do some traditional ideas about them. Perhaps some of it is “slippery slope” reasoning, but for example: why should something have a static make-up (gender), how can anyone reasonably think that Mercury affects refrigerators or that cats affect luck, and if what we imagine to be “a person” is actually a tree of possibilities spread out over space-time, why do we think we’re able (at this time) to compress all that into a container?