Weakening an argument is a standard job on the GMAT. Since we encounter arguments every day — in newspaper columns, in advertisements, on television, and even in conversations with our co-workers about where to have lunch — you might think that weakening them is something we’re all accustomed to doing, and therefore this should be easy on the GMAT. Part of the reason it’s not so easy is that a lot of people don’t think critically about the arguments they encounter, and thus aren’t practiced in trying to weaken them at all. But part of the reason is that the one of the main ways most people try to weaken arguments in real life isn’t available to you on the GMAT.
Let’s look at an argument and explore the differences between how we could weaken it in real life and how we could weaken it on the GMAT.
Low taxes stimulate the economy, creating more taxable revenue and increasing the amount of taxes the government collects. Therefore, any country that wants an effective tax system should lower its taxes.
What else you can do inside qs leap ?
Weakening the Argument – Real Life Version
So how would you weaken this argument? Many people would begin by challenging the premises. That is, they would question whether low taxes will really stimulate the economy. Or they’d ask how much additional taxable revenue would really be created? Or they would suggest that even if more taxable revenue were produced, it wouldn’t compensate for the lower rates themselves and the government would ultimately collect less revenue. I offer no opinion here whether the premises are true or false because it doesn’t matter. The point is that challenging the premises of an argument is completely legitimate in real life. You may be right or you may be wrong, but the truth of the premises is always a valid thing to explore in this context. At the least, most people would ask for some evidence that the premises of the argument are true, rather than just accepting them at face value.
But accepting the premises at face value is exactly what we have to do on the GMAT, and this is the big difference between weakening real-life arguments and weakening GMAT arguments. On the GMAT we must accept the premises of an argument as true. In real life we are free to reject the premises of an argument if we believe the argument is proceeding from false facts.
What else you can do inside qs leap ?
Weakening the Argument – GMAT Version
So how would we weaken this argument on the GMAT if we can’t challenge the premises? We attack the assumptions instead. That’s the key to weakening an argument on the GMAT — you have to attack the assumptions that the argument relies on. Assumptions are like premises because they also provide reasons to support the conclusion of the argument. But premises are explicitly stated, and assumptions are by definition unstated. So our task is to find the unspoken parts of the argument, i.e. the parts that have to be true for the argument to work.
Let’s list some of the assumptions the argument is making, and how we might criticize them.
• Assumption: An effective tax system is one that maximizes tax collection revenues.
Taxes serve many purposes. Sometimes taxes are used to provide incentives for certain behavior — they reward some things and penalize other things. A tax system that collects a lot of money might not be considered effective if it doesn’t provide the incentives desired by the government
• Assumption: Countries don’t currently have low taxes.
The argument claims that low taxes will increase tax revenues and then concludes that countries should lower their taxes. But what if a country already has low taxes? Then it doesn’t necessarily make sense to lower them further. What happens when we get all the way down to zero?
One Final Point
One last thing to point out is that attacking assumptions is not only a valid tactic on GMAT arguments, but on all arguments anywhere. In real life you can certainly attack the assumptions made by an argument as well as the premises. Just remember that any time your task is to weaken an argument on the GMAT (which would be for Critical Reasoning Weaken questions and also for the Argument Essay) you have to set aside whatever doubts you might have about the premises and focus all your attention on finding reasons that the assumptions are questionable.
