Green and Red Flags for Intellect

How to tell who's who

As a nerdy Zoomer, I’ve often found Reddit threads of people trying to discern subtle green or red flags for people’s intellect. The vast majority of these devolve into the same old tropes: “smart people don’t talk over you” or “they don’t speak about every issue”. These are not that interesting and pretty straightforward. So instead I’ve decided to assemble a list of green and red flags that are non-obvious but still decently indicative of someone’s intellect.

Note that you should not misinterpret this thread. Having a green flag is indicative of intelligence, while having a red flag is indicative of unintelligence. But do not assume the antecedent! Not having a red flag is not strong evidence for being smart and not having a green flag is not strong evidence for being stupid. For an obvious over-the-top example of this, an inability to calculate 3+7 is a surefire sign that someone isn’t smart, while an ability to answer with “10” is still not a sign of a clever individual. Likewise, someone with a math PhD from MIT is almost surely smart, but having said degree is not necessary for intelligence.

And if these feel familiar to you, it’s likely because I posted this as a thread to Twitter months ago.

Green Flags:

Green flag: using "percentage points" correctly (as opposed to "percent"). Common when discussing econ-y material. Quick example: a fall from 75% to 25% is both a 66% fall and a 50 percentage point fall.

Green flag: using the terms "probably", "more likely than not", "unlikely", "in most cases", "rarely".

Green flag: self-ironic and self-depreciating statements.

Green flag: shutting down arguments faster when realizing that the disagreement at hand is about a definition, and not necessarily very substantive. This requires a good amount of willpower when arguing, so is a pretty telltale sign of intellect.

Green flag: being high on decoupling. The ability to admit that evil people can be intelligent, or that good people can be dumb. Not falling prey to the "all good things are good together" or "all bad things are bad together" fallacies.

Green flag: the ability to repeat someone else's argument without strawmanning it.

Green flag: agreeing to bet on their beliefs. This is a sure sign that the person is not full of it.

Green flag: honesty about their own incentives in the conversation or argument.

Green flag: Not confusing intentions with actual effects (suggested by @PrivB4_).

Green flag: wanting to hear counterarguments (suggested by @jsperera1).

Green flag: qualifying their statements with scope conditions. E.g. “when X, Z, B, then Y holds”. Or at least a good ol’ fashioned “ceteris paribus” (suggested by @jsperera1).

Green flag: finding the crux of the argument. Instead of going in circles, trying to figure out what in particular could change the other person’s mind.

Green flag: looking for base rates. Instead of thinking that their child is at risk because of a recent school shooting, asking themselves how likely a shooting is in general.

Green flag: remembering the existence of opportunity cost.

Green flag: telling you how their probability of an event has changed after new information. In other words, Bayesian updating.

Red Flags:

Red flag: saying that you're "just stating the facts". Facts mean nothing without a narrative, those making this claim are never "just stating the facts”.

Red flag: asking questions about people's behavior in an accusatory tone. Often with the implication that the person in question is stupid ("why would he ever leave that job?"). Smart people will try to *explain* decisions with someone's beliefs/logic.

Red flag: using the terms "always", "never", "no chance", "definitely". Only a Sith deals in absolutes.

Red flag: refusal to engage in hypotheticals. Hypotheticals are often useful (and necessary) to test the logic of people's arguments. Running away from them is a good sign that someone is full of it.

Red flag: not appreciating first approximations, dismissing arguments or evidence because "you can't know for sure".

Red flag: verbosity. If you notice that someone is unable to summarize their key point in a few sentences, then that's a bad sign.

Red flag: arguing against a point by saying that it's "just theory". Theory is important for understanding the logical consistency of different positions.

Red flag: demanding you prove something with certainty before they buy into it.

Red flag: messing up levels vs rates (thinking "inflation fell" means "prices fell").

Red flag: assuming the antecedent. Thinking that *not having* a green flag from this list is a red flag. Or thinking that *not having* a red flag is a green flag.

Red flag: "if he's so smart why can't he...". Intelligence does not mean omnipotence.

Red flag: latching onto a tangential part of the conversation that they have better insight on. E.g. in a conversation about whether printing money causes inflation, they go on a long rant about measuring inflation because they worked at the BLS and have expertise there.

Red flag: presenting anecdotal evidence as a counter to statistical aggregates (suggested by @jsperera1).

Red flag: forcing spectrums into dichotomies (suggested by @jsperera1).

Red flag: thinking cynicism implies wisdom. The assumption that believing in the worst case scenario makes you “more real”.

Red flag: identifying with one’s beliefs. Taking counter-arguments as personal insults.

Red flag: zero-sum thinking. Assuming that one’s gain is always another’s loss. Radical political activists are often guilty of this.

Please suggest more below. I’m very welcome to the idea of making this an ever-expanding list.