All of humanity's problems stem from man's inability to sit quietly in a room alone. - Blaise Pascal

I would define a "problem" as anything that prevents a human being from having a long, fulfilling life with minimal suffering. Perhaps we could extend this further with immortality, but I'll leave that aside.

But if we consider that definition, then yes, there are many problems. They range from anything from physical to psychological needs. To feeling valued by society. To feeling fulfilled in relationships. All are "problems" IMO.

Because human beings exist in a social context, many of these problems boil down to a social contract between the individual and society. And discussions around the evolving nature of that contract in a way to minimize suffering is essential. With various philosophical problems like whether one groups increased suffering is OK if it minimizes average suffering.

For example, is it OK that we minimize the suffering of many in the near term by producing carbon? Knowing there may be longer term issues and externalities?

Is a war that will cause short term suffering OK if it liberates a group of people and may cause a decrease in longer term suffering?

At risk of sounding like a Scientologist (I am not) I’d say if people didn’t have problems they’d make some for themselves. For instance whatever you have or don’t have you can want something more, less or different.

We have "problems" only because we (humans) have decide to classify them as such. Do you think dogs (or trees or stars) have problems? Is losing my job a problem? If so, how is that different than a meteorit hitting the earth? Is the latter a problem or just a "natural thing"? Why is not the former a "natural thing" as well? Human beings are as natural things as meteorits.

Assuming a mechanistic worldview, how could our world not have many grievous problems? We clawed our way from the mud and for all our cleverness, we are still the product of a messy and imprecise evolutionary process. ‘Good enough’ is what results, not perfection.

Genes have errors, leading to cancer and mental illness. We war over resources and ideologies because we are running software that derives from vicious apes.

The world doesn't have problems, people do. The reasons are as innumerable as the problems.

I suppose you could then say the world has a people problem?

I think the natural order of things is chaos rather than peaceful order.

Looking back at this question, I realize that there is most likely not a 'basic' answer. My apologies, everyone.

Finite resources + human nature

My naive answer is that it's fundamentally an innate fear of death.

Humans sin - Jesus

self-aggrandizement and greed.