Determining whether you have too much stuff is a personal decision, and also often involves comparing what you do have to others. There really is no objective measuring stick capable of defining how much stuff a person should have. In a Western culture obsessed with consumerism and material wealth, some might ask if it would even be possible for anyone to have too much stuff. After all, not having enough is often much more problematic for people than having too much. Millions of people around the world probably wish they had more, as they have the opposite problem. The problem of having too much stuff is definitely a luxury of the rich.
The comedian George Carlin developed a routine around the concept of "stuff." Carlin's belief was that almost everyone has a large supply of stuff, possibly too much, but we insist on storing it in smaller and smaller containers of stuff. When our closets become full, we move some of it to drawers. If we need stuff for vacation, we put some of our original stuff in suitcases. We even buy smaller versions of stuff just to have on hand when we leave our big stuff behind on a trip.
The actual question about "too much stuff" goes much deeper than it may appear. What we're actually discussing is the accumulation of material wealth over a lifetime. You might ask if there a logical stopping point for accumulating things, such as when we find personal fulfillment in what we already own. The idea of too much stuff suggests that a saturation point has been reached and the rest of one's stuff is unnecessary. Obviously, most people have more stuff in their closets and storage containers than they will ever need to get through a typical day, but is it too much?
Some may say that a umbrella serves no purpose until it rains. In that same sense, much of what we accumulate over the years may no longer appear to have a purpose, but one day it might. We may have too much stuff to manage at any one time, but that might be more a question of not enough storage space. Many people have a pack rat mentality, which means they will not part with a single item without a court order or a decent fight. For them, the idea of "too much stuff" would sound alien. Others prefer to eliminate stuff and clutter as soon as it threatens to accumulate and affect their peace of mind.
It may be possible to have too much stuff if you no longer find satisfaction in what you have or in getting it. Collectors often feel a compulsion to continue acquiring items until they no longer bring a sense of satisfaction, and the collection process becomes more of a hindrance than a hobby. When contemplating the idea of having too much, you should consider if all of these material possessions are providing a sense of accomplishment or if they are acting as a barrier to your true happiness and satisfaction.