Keynesian economics is valid

Let me address your arguments point-by-point."The market system is self is fundamentally flawed for operation in a 21st century climate"Granted. "How ever the Keynesian model which centers around Aggregate demand as its core measurement of economic health is tied to the economies ability to continuously grow. Keynesian economics, as a product of the 20th century's is based on 20th century understandings of global resources. Despite the Global Economic depression of the 1930's ( which was not caused by any one single factor alone) the last two-centuries have been marked by nearly unhindered economic growth." Several errors. AD is not a measurement of economic health. Actually, AD = GDP. And growth over the past two centuries has in fact been hindered: see the 1930s, and the 1970s. "any point a Market short fall arrives the Government will step in, spend a lot of money and velocity of money ( the circular flow) will, stimulate the economy." Not any point, just depressions and recessions. Also, how can government spend "velocity of money?" So you know, velocity of money is primarily used by Monetarist models, not Keynesian ones."Sstimulus for the purpose of stimulus in the economy is a simulation of economic growth but creating artificial forces in the market either by artificial demand ( government buying ^%$# up) or artificial production by subsidizing production under specific terms-or-even the subsidizing against a product."Due to further grammatical crimes (felonies? :), I can't tell what this means, but I assume it means "Stimulus is bad, when government buys things the market is distorted." Even if these "market distortions" cause issues, is it not better to try to prevent or mitigate a crisis? Would you not try to prevent or end the Great Depression? I think I would. "Of course the governments can build Roads and of course they can fund Research and development. But we are talking about the concept of building a road for the sake of building the road in order to stimulate the industries related to road building. This practice can only simulate market forces otherwise at work. The end product is a simulation of growth while we wait for the market system to find a new resources to exploit, a new industry to form or any new economic force to generate more wealth."This is rather incoherent, but I think it means that the public sector alone cannot support an economy. I agree. But the private sector cannot support an economy on its own either. Government must assist. " Keynesian economics is rooted in an age of progress fueled by resource consumption, a set of market parameters that are no longer met in the economic reality. In order for Keynesian model to be successful the economy MUST grow continuously. But that is no longer a viable option."This is very vague. Please provide a concrete argument so I can refute it. "Our modern economic reality is one where Global resources are continuously being exploited to fuel an ever more difficult to achieve rate of growth. In China, there are entire ghost cities... built with no residents. http://www.zerohedge.com...... Which is being done in an effort to Stimulate economic consumption...but it is widely known that China is hitting the end of its ability to create artificial demand. "See my debate here (http://www.debate.org...) to see that resource consumption is not necessary for growth. I am not a supporter of Chinese ghost cities. Not all stimulus is well designed. But the right stimulus can be profound. Keynesian stimulus (WWII) ended the Great Depression."So this [WWII] is the most over used Keynesian talking point in existence. Even though there is truth that the total mobilization of resources for war ended the Depression in the Victorious United States ( we where the only ones who really came out on top.) The set of circumstances which allowed for that event CANNOT BE DUPLICATED."Hey hey hey. I don't want another world war. But this kind of stimulus - massive spending in industry - can help.Let me address "IV - Monetary policy" all at once. I assume this objection is the classical "fiat money will ruin us all. And those federal reserve b*st*rds too." Fiat currency is used in literally every economy on earth. In the US, it has been used for around 100 years. Fiat money has not ruined our economy. It has given our federal reserve the power to mitigate crisis. According to Friedman (most certainly Anti-Keynesian), the Great Depression was caused by the fed not doing enough. Fiat currency gives the fed power, which even anti-Keynesians want. Non-fiat (gold standard) money would destroy the fed. Every recession would be as bad as 2008 - or even worse, 1929.Also, here is my response to "V - GDP." Keynesian economics does not just support a paper economy - it supports a real one. Keynesian stimulus ended the great depression, arguable the darkest period in peacetime history. Keynesian economics meant that starving American families could put bread on the table. Look at the post-WWII economic miracle, experienced in the United States, Europe, and even Japan (and far later, China).Overall RebuttalHere is the thing that you misunderstand. Keynesian economics does not intend to "prop up a paper economy on wasteful and destructive stimulus." This is simply untrue. Keynesians really want government to stimulate the real economy, when real people are hurt by misfortune, when there is no other option.Explain to me how this scenario is harmful. The economy is in a severe recession. Government chooses to build some highways. The government hires construction, materials, raw materials, and transportation companies and workers. This creates decent jobs, and increases GDP. So now, the economy has grown (greater AD) and has more jobs. What is wrong with this picture?Keynesian economics is intended to stimulate the economy when it is in dire need. And it has worked: see WWII.Reiteration of Arguments 1. Keynesian economics is essentially a consensus among mainstream economists. This is not ad populum, because these are qualified experts.2. While this is overstated, Keynesian economics ended the Great Depression.3. Government can perform essential functions, like building highways, creating things like the Internet, and making achievements like those of NASA. Not to slam the private sector, but no private company could or would have done these things.4. Simple mathematical/analytical exercises, like the highway parable, show why well designed stimulus works. Not all stimulus is well designed, but at its best, Keynesian economics has great potential.5. Keynesian economics does not cause recessions by over stimulating the economy. Keynes himself wanted government to cut spending and balance the budget when not in a recession.6. The US economy can easily handle more debt. And the debt/GDP ratio overstates our debt by at least 2.7 trillion dollars.And next time, use the built in spell check please. It makes your arguments more comprehensible. Or don't: more points for me.Back to you, Con!