Since my opponent forfeited the debate, I suppose I'll go first.
Before I begin I will define Capitalism and Socialism.
Capitalism: an economic and political system in which a country's trade and industry are controlled by private owners for profit, rather than by the state.
Socialism: a political and economic theory of social organization which advocates that the means of production, distribution, and exchange should be owned or regulated by the community as a whole.
I have several arguments as to why this is true.
First, Capitalism has been responsible for plummeting rates of poverty over the last few hundred years. As Capitalism spread across the world and more people had access to free markets where their labor and time belonged to themselves and market forces of allowed for the creation of new products and of increased wealth, extreme poverty rates plummeted to near nonexistence. You can view statistics on poverty rates over time here https://fee.org/media/28562/chelsea-new-02-1-790x350.png?width=600&height=265.8227848101266
This is particularly true over the past 20 or so years. the World Bank reports that from 1990 to 2015 the number of people living in extreme poverty has dropped by slightly over a billion people.
Contrast that with socialism which has wrought nothing but poverty, death, and economic devastation wherever it's been tried for any significant period of time. I challenge my opponent to provide one singular counterexample.
On my end:
and many others
Capitalism has also seen massive increases in individual wealth.
Since the mid 18th century when the powers of Europe first adopted capitalism the average per person GDP has risen massively. Examining the chart that I will provide here https://fee.org/media/28563/deirdre.png?width=600&height=509.8265895953757
shows us that personal wealth had been stagnant for nearly a thousand years then the age of Capitalism begins and wealth explodes in an unprecedented way.
Point number two addresses socialisms 100% failure rate. There are many reasons as to why Socialism's collapse is inevitable, but the one I want to focus on right now is very simple. Socialism fails because it cannot set a price. Socialism hinges on price controls. It necessitates that the government or the community ensures that those that produce goods can't charge what they deem to be too much. This overly simplistic analysis of how prices work was what led to the economic devastation of East Germany. Simply put, a price is determined by supply and demand. There is always a real price for any given good or service. The government can, in theory, step in and attempt to force the market to bend to its will; but what every socialist country has eventually discovered is that the real price is always running in the background. Eventually, reality asserts itself and the illusory economy set up by the government implodes. This happens in one major way. When the government sets a fake price that causes producers to lose money, they stop selling their goods. At least officially. As was the case in East Germany, it eventually became the case that the only place you could buy your goods was on the Black Market. A place free from government meddling where the real price was allowed to operate. This market is untaxed which causes a sharp decrease in revenue for the government.
This price interference has another major drawback. It removes the stoplights that investors use to make decisions. The real price allows people to know what goods and services to invest in. When the government is artificially setting the price, no one knows what goods and services are really going to take off and make money. These investors can be foreign, domestic, or even the socialist government itself.
Moreover, the high cost of socialism for governments tends to lead to hyper-inflation and economic ruin. When, as former British Prime Minister Margaret Thatcher once said "you eventually run out of other peoples money" and socialist governments become strapped for cash, they just print more. This is exactly what happened in Venezuela and East Germany. Printing more currency devalues your currency leading to massive levels of inflation to the point where you need wheelbarrows of cash to buy a loaf of bread. When the government stays out of the market this isn't a problem.
In short, Socialism cannot bring prosperity because it destroys the market functions of private property. Under socialism, private ownership of the means of production no longer exists, and thus there are no market prices for capital goods available. Institutionally, socialism consists in abolishing the market economy and replacing it with a planned economy. By doing away with private property of the means of production, one wipes-out market information and valuation. Even if the socialist administration puts price tags on consumer goods, and the people may own consumer goods, there is no economic orientation about the relative scarcity of capital goods.
Capitalism, with its emphasis on personal private property and market forces, allows for the coordination of the division of labor and capital which history shows us, is better for everyone.