We all know we’re not supposed to judge people. We also know that everyone does it anyway. It’s part of life. But how do you personally go about deciding how smart someone is? Do you have any ideas about what particular aspects of someone’s personality should be taken into account when considering their intelligence? And does this generally affect your overall opinion of the person?
I find the slack-jawed yokel/mouth breather stereotype to be pretty accurate.
If someone isn’t self aware enough to close their mouth when they’re, say, filling their tank, it’s generally a safe assumption that they aren’t the brighest bulb.
I know that doesn’t help really judge people’s intelligence, but perhaps it can help identifying stupid people.
I don’t know how else you would do it outside of basic conversation. Of course some people might be better or worse in various ways, but still usually someone is “intelligent” or not.
I would hold my judgement for someone who was a highly knowledgeable blathering idiot. For instance, a college professor who had odd political ideas and seemed obsessed with it regardless of how illogical it might be. Still probably intelligent, but totally separated from reality, so…
If someone starts telling me how much money they make, they immediately go down in my opinion (possibly not a good measure of intelligence though). If they watch things like Big Brother, another bad sign. Read Dostoyevsky- or even heard of him- great sign. Know what mnemonic or shibboleth means- top of the world.
And of course if they are members of SDMB…
Usually current affairs. I suppose I don’t really care about how intelligent someone is, but how knowledgeable. While the two things do usually go hand in hand, I’ve known at least one person with sub-100 IQ intelligence who was very aware and curious, and several well educated - even “genius” level - people who know very little about the world outside their own lives.
And I just realised I didn’t answer the OP in any way, thus revealing my lack of intelligence to the board.
But jjim, I always enjoy your posts anyway. 
If they read women’s magazines. I guess it’s not intelligence as much as, well, something else, but if someone reads women’s magazines it’s pretty much guaranteed that I’m never going to have an interesting conversation with them, ever.
Ah, see, now I don’t really care if they are up on current events. I mean, they should have some idea, but I’m not too picky.
I have several ways:
Well-read. This is the easiest one to judge. Drop one or two references into the conversation and see if they pick up on them or look at you funny.
Good vocabulary. Also easy.
Quick on the uptake. Drop a joke and see how fast they get it.
Etc.
So how stupid do you judge me to be, Anaamika dear? 
What sort of intelligence?
When I was seventeen, I read Dostoyevsky, but I only did it because I thought it was cool. Not intelligent.
I know people who are brilliant at mathematics. Obviously intelligent, but I’m awful at maths, and don’t relate to them.
Then again, I have a bit of a standard test: if somebody laughs at:
“What’s the definition of 668?”
“The neighbour of the Beast”
… I like them, and think they’re intelligent. It’s a totally flawed test of course, and the mathematics genius might find that joke childish, unfunny, or simply not get it.
I judge them on their humor level and how well-versed they are on current events and how quickly they can learn new things.
By whether or not he/she agrees with me.
First, a good look at their eyes. It tells you a lot.
Then, just the sound of their voice. Don’t know how to describe it… it isn’t the pitch, nor the vocabulary, nor the accent… it’s something in the timbre and intonation. Sort of like the eyes thing – you can just tell. I’ve been known to tell people they “have an intelligent voice” and get a response that basicly said they thought I was even stranger than I really am (this would be over the phone, duh!)
Then, some basic conversation. Mostly, how well can they explain a concept that they understand themselves (or at least should understand); how well do they field out-in-left-field questions about the topic of discussion; and can they take a joke and throw it right back at ya 
I don’t know that I necessarily agree with this one. I mean, if they read them religiously, possibly, but sometimes women’s magazines are nice to pick up because they’re a bit of light reading when you need a break, plus some of the stuff can be fun to laugh at.
I dunno, From the Straight Dope[sup]®[/sup] Home page
I try not to judge based on first appearances: I’ve been wrong before.
I guess for me it boils down to intellectual curiosity. In other words, it doesn’t matter so much what you’re reading or what political beliefs you have, but that you’re curious about the world around you and want to learn more about it.
Reading plays a huge part in this. I’m not going to respect someone as much if they limit themselves only to Danielle Steele novels, but it’s better than nothing. It’s very rare to come across a smart person who doesn’t like to read anything.
Being aware of other cultures. I’m not going to scorn the person who doesn’t use chopsticks, but someone who knows nothing about the culture, cuisine and beliefs of other cultures is someone who lacks that cruical curiosity.
Being well-informed about what’s going on in the world. I don’t think it’s important to know all the names of the world leaders, but if you give me a blank look when I mention current conflicts, it’s a bad sign.
For me it boils down to: Are they a “type”? Or are they obviously an individual?
Yes, there are intelligent “types”, eg: professors, programmers, historians, researchers, etc. But as a rule, I find that the more an individual differs from type, the more depth and sensitivity and, uh, intelligence they tend to have.
[size=1]NB: For purposes of this thread, you may consider non-conformists to be yet another “type.”
Another way to look at it is: Are they informed about other fields, areas, disciplines, etc., than their own? That ferdamnsure is going against type, in our tracked, nose-to-the-grinder society.
I attended one of the nation’s top engineering schools, and one thing I learned is that there are some mighty smart people who enjoy some mighty stupid types of entertainment and media.