Capitalism is defined as the economic system or ideology that is primarily based on private ownership of the means of production and their operation for profit.
The definition is rather straightforward across all dictionaries. What has become rather problematic is the perception of the meaning of the word. Definitions change based on cultural narratives and this can lead to much misunderstanding.
The first and foremost means of production is the individual himself. Without the individual, nothing happens. When many individuals come together and produce something then we are still within the realm of capitalism since everyone wants to make profit at the end of the day. We take one substance and turn it into another in order to exchange it. Nothing is or can ever be valued the same.
The creation of profit is rather inevitable based on the laws of nature. If everything was valued the same, everything will be valued to zero.
Take for example a bucket of water. In times of drought, that bucket can be very expensive for someone that is thirsty. In a rainy place like Ireland, that bucket is probably worthless. The planet is governed by different climates, cultures, ecosystems and temperaments that make each unique transaction profitable. A bucket here is not the same as a bucket over there.
This different perception in value is what creates capitalism. Even is by some magical means we were able at the very end of each day to balance all values down to the same price, everything will be worthless. There would be no need to produce a table if an apple is worth the same. Eventually the system will collapse — and this is what exactly happened with all socialist systems. They failed because they were more inefficient compared to capitalism.
It is my firm belief that natural law provides the constituents for capitalism for flourish. Every single species arounds us fights in order to survive. Groups band together in order to take over on other groups. Those who survive go on to make even more adaptive individuals. This goes on and on. Survival is the only game in town.
When we want to have our own kids then we are expressing capitalistic tendencies. We value our own genes more than we value others because this is how nature dictates our physiology from the time we are born. We desire a specific brand over another because we value one over the other. We like 'Book A' instead of 'Book B' because the one is superior from the other. There is no other way for humanity to exist.
Nonetheless, this allegory of the concept of capitalism brings a sense of unfairness to most people. The reason is rather simple. Nature doesn't care about all of us. It creates a lot of variations so some will go on, not all. The selection is random. This is how we get mental disorders, genetic diseases or geniuses. Only a very few matter due to the way natural selection works. The rest are rather worthless combinations, failed experiments based on the given environmental parameters that were introduced.
Ironically, the very crowd that is awry about capitalism is the one that defines it. Whether it is famous pop-star, a brand of cigarettes or a booming shitcoin the crowd never wants all things to be equal. Individuals want to distinguish themselves through profit. We are defined by value, by own capital. Whether that capital is intellectual, social or financial is rather irrelevant.