Ignorant opinions
There are many things about which we don’t know much, but that ignorance doesn’t stop us having an opinion
An indoor swimming pool. The smell of chlorine in the air is palpable, and the kids are coughing. You’re not the only person to notice, and another parent asks what you think an acceptable concentration of chlorine in the air should be. You take a wild guess: “4ppm?” The other person seems to be in the know: “It’s 2ppm now,” she says. “Oh, then it should be less,” you state.
There doesn’t seem to be anything amiss with this conversation. You are not a chemist or a health and safety expert, so you had no real idea. You nevertheless gave an opinion based on your superficial knowledge about concentration levels of noxious gases, offering a vaguely plausible number. If you had had to estimate how much chlorine there actually was in the air, you’d probably have suggested something like double your guess at the acceptable level.
Equivalent or perhaps not so equivalent
Now picture a very similar conversation about a different subject: taxes. You ask a friend, if the total personal income tax revenue is 100%, what proportion of that would be acceptable for the top 1% earners to pay. “20%”, she says. Asked how much she thinks they actually…
