The funny thing is, this example isn't even true. Knowing that all Secret Service Special Agents are US government employees does not allow you to logically conclude that some US government employees are Secret Service Special Agents -- you also need to know that at least one Secret Service Special Agent exists!
For example, it is true that all humans living on Mars are US government employees -- but not at all true that some US government employees are living on Mars.
If you take the question abstractly enough, with zero a priori knowledge, then the example becomes valid again. There may not even be any US government employees at all, anywhere.
Ever taken an IQ test? One reason for phrasing the questions in terms like "All gribs are freebles, and some freebles are blorts" is to avoid that kind of problem.
Obviously, the intent with all test questions of this nature is for you to treat all nouns as abstractions.
s/Secret Service Special Agents/American hijackers/
s/U.S. government employees/Americans/
We therefore conclude that "Some Americans are American hijackers." The logic's airtight; it comes from a secret service test designed to evaluate logic ability.
It seems more than one HN user finds it amusing that this guide covers "rudimentary" things like predicate logic and word problems. Keep in mind that these are the skills the Secret Service wants their applicants to actively get better at before applying; it just so happens that already having these skills are common in the HN community.
I'm sure the community of Secret Service applicants finds the skills they are good at for which the HN community needs to actively get better at equally amusing. Social aptitude and physical fitness for example...
Maybe I'm getting old but my preference is to not cast stones at communities that are different than mine.
Why is this surprising? The Secret Service is notoriously difficult to get into -- its acceptance rate is 1% compared to Harvard's 6% -- but the majority of the requirements are not assessed by a written test.
It's somewhat like trying to ascertain anything about MIT based on its swim test requirement.
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[ 3.2 ms ] story [ 59.2 ms ] threadInvalid conclusion: All government employees are Secret Service Special Agents.
Valid conclusion: Some U.S. government employees are Secret Service Special Agents."
For example, it is true that all humans living on Mars are US government employees -- but not at all true that some US government employees are living on Mars.
Obviously, the intent with all test questions of this nature is for you to treat all nouns as abstractions.
Some humans living on Mars were born on Venus. <-- False
s/U.S. government employees/Americans/
We therefore conclude that "Some Americans are American hijackers." The logic's airtight; it comes from a secret service test designed to evaluate logic ability.
Suddenly the TSA makes sense.
I'm sure the community of Secret Service applicants finds the skills they are good at for which the HN community needs to actively get better at equally amusing. Social aptitude and physical fitness for example...
Maybe I'm getting old but my preference is to not cast stones at communities that are different than mine.
<eats french fry>
It's somewhat like trying to ascertain anything about MIT based on its swim test requirement.
One does not want to mess with organizations that have "part 731" of anything.