Using misleading comparisons is a foundational strategy for all forms of propaganda–science denialism, pseudo-science, and political. There are a lot of ways this is done. I divide them into two main categories: Numerical and Non-numerical. This page will focus on the most common non-numerical misleading comparisons.
Benefits vs Costs
The most common misleading comparison is to list the benefits of the preferred policy/technology/method and compare them to the costs/downsides of the vilified policy/technology/method. Gee, I wonder which one is going to look better?
The correct way to compare two things is to ensure that we are comparing the same properties. We should compare benefits to benefits and costs to costs, or net benefits to net benefits.
At this point it’s a good idea to remind ourselves that benefits without costs do not exist. This is the fundamental lesson of economics and evolutionary thinking. For every policy or every trait, there will be trade-offs. Everything is a matter of trade-offs. And so, anytime someone tells you there are only benefits (a) they are lying (b) try to figure out what the trade-offs and costs are. Always ask, “compared to what?”
Ideal vs Real-world
Another common strategy is to compare how policy/technology/method works in theory vs how the competitor works in practice. Everything works perfectly in theory. Nothing does in practice. This method of comparison rigs the game.
The correct method is to compare in theory to in theory or in practice vs in practice.
Potential Risk vs Actual Risk
This strategy is a close cousin of the other two and gets used two ways depending on what outcome you want. If I favor something I’ll say that it has very low potential risks compared to the actual risks of the thing I’m against. However, it’s most commonly used against new technologies the other way. Anti-GMO make a lot of noise about or inflate the possible risk of the new technology because “we just don’t know!” This is a perverted version of the precautionary principle.
The error here is to forget about actual risks of the situation for which the technology was developed. For example, in the case of GMOs the risks of crop failure and starvation–especially with climate change–are not just imagined, they are real. They will happen. Why do we give more weight to imagined risks when the real risk are…well…real!
This error in thinking was front and center when anti-GMO advocates blocked and destroyed golden rice (vitamin A enriched rice). Without the golden rice we know for a fact that thousands of the most vulnerable children will go blind every year. The possible risks of golden rice are very moderate if anything at all. The choice is easy when we correctly frame the comparison.