Critical Thinking, Skeptical Thinking

Not enough people bother to use critical thinking skills, or what I call “skeptical thinking” skills. They accept most everything anyone tells them at face value, or they weigh incoming information only against existing biases and preconceptions.

Let’s do an example, and it’ll be a fun one. I swear.

I have met several vegans in life. Most of them (the ones I met, not all of them on the planet) became vegans for philosophical reasons. However, the thing with humans and philosophy is that we have some kind of need to make other people accept, and convert to, our way of thinking. Well, trying to convince me to go vegan because cows are such gentle creatures just won’t work. I’ve met cows. They were yummy. So, a lot of these vegans would switch tactics to something I completely hate and despise, which is whipping out “compelling” arguments that they think will sway me, when in fact they’re sitting there lying the entire time. Mind you, I’m fine with them being vegan and never tried to convert them, but they’re out to save the cows or something.


One of the newer arguments, as our news channels become overloaded with news of droughts, focuses on water consumption. I do love this one, and we’ll use the example at It can, the argument goes, take up to 2,000 gallons of water to produce one gallon of milk. Meaning, cows drink a lot of water, but plants – my gosh, they practically sip the stuff. Notably, that website doesn’t mention how much water plants need. Well, this argument falls apart in the face of critical thinking. We’ll focus solely on the water usage part of the argument, since this is really about using critical thinking, not the argument itself.

The idea here is water efficiency. Given a certain amount of water input, how much food – e.g., calories – do I get out if it? The more calories I get per input gallon of water, the more efficiently I used that water.

A 1000-pound beef cow will drink about 11 gallons of water per day in 80-degree weather. 1000 pounds is a typical slaughter weight, and obviously the cow isn’t that weight from birth. It takes on average 13 months to get a cow to that weight, so by my calculations you’re looking at about 3,000 gallons of water. Depending on the breed, that cow will yield about 67% edible meat, or about 670 pounds. You get very roughly 665,000 calories from that much meat, understanding that there’s a decent amount of averaging and rounding in that number. So, about 220 calories output per gallon of water input.

I decided to go with pinto beans as my vegetable comparison. They’re one of the higher-calorie veggies, and they offer a lot of protein, like beef, and a small amount of fat. It’s nearly goddamn impossible to get actual numbers on these things, but a plant seems to want about .01 gallons of water per day, more as it nears maturity. They need about 120 days to mature, so if you extended that out to a 13-month cycle (for equivalency with the cow), you’d get about 4.1 complete crops and use about 10 gallons of water. You get about 150 beans from that growing cycle, which produce about which yields about 300 calories. That’s about 30 calories output per gallon of water input.

So cows are a hell of a lot more water-efficient, producing 220 calories per gallon versus 30 calories per gallon. So, with critical thinking, we can eliminate that “water efficiency” argument. There are other arguments, of course, and those should all be considered just as carefully.

So, has my argument swayed you a bit? Not the cow argument; I don’t care what you eat. The critical thinking argument. The next time someone makes some off-the-cuff argument, will you consider it more carefully before you take it as gospel truth?

Well, if this article has swayed you even a little bit, then I’ve completely failed.

I didn’t cite a single source in my entire argument. I just made up some of the numbers (researching is hard) and did math. And some of that math was wrong. 10 gallons per bean plant? Really? You’d probably kill the thing with that much water.

And when you make an argument like this you can’t just conveniently focus on one aspect of the argument. Beans don’t eat food. Cows do, and that food takes water, also. Cows also fart constantly, producing copious amounts of methane. Beans don’t fart, but people who eat them do, so there’s methane either way. How much? That’s the point: People like sound bites and easy numbers, but nothing in life is easy numbers.

Which is why skeptical thinking is so important. If someone makes some seemingly detailed argument like this, and doesn’t offer reliable sources, ignore the entire argument unless you’re going to recreate it using your own numbers. If they do offer sources, check them. Would you trust the American cattle industry to provide accurate, unbiased numbers about cows? I wouldn’t.

People are out to sway you and change your opinion constantly. Politicians do this habitually. They know you won’t check, and so they can toss anything they want at you. All they have to do is find your particular weak point and then target an argument right at it, whether it’s factual or not. And we just slurp up whatever they tell us without bothering to fact-check one iota of it. It’s annoying, it’s dangerous, and it’s wrong. It makes you no better than the cows, although probably less tasty.