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Never trust a system that seems to be working

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Re: Never trust a system that seems to be working

#251

Post by conradfr »

ranger207 wrote: post #246
conradfr wrote: post #242

Earlier quoted context omitted.

How does that make sense? You write the same amount of text in the end.

The dopamine hit from click the send button can help overcome the ADHD tendency to wander off task. Plus, even if you have half an essay posted to Twitter and still get bored, it's much more difficult to just leave it halfway finished than to leave an unposted blog post in your drafts. And besides that, I'm really not sure why people get so upset at people putting content into the world. Wasn't the point of the inter…

Personally I don't care too much.

But on the other hand I have ADD and there's a chance I get bored with a twitter thread and move on before finishing it while a blog post allows me to keep it open in a tab and read it in steps.

Re: Never trust a system that seems to be working

#253

Post by bombcar »

Gordonjcp wrote: post #243
bombcar wrote: post #127

Earlier quoted context omitted.

Yeah, any design is going to be various trade-offs, and you have to understand them (and how they may relate to your mission) when determining what to do and what would be a bad decision. For example, cars have "fail open" brakes but have independent cylinders so that it is relatively hard to have all four wheels fail at the same time (older cars had single master cylinders) - and one of the tradeoffs is that people…

Pretty much every car made since the 1980s has had dual-circuit brakes with usually one front and one rear wheel cylinder on each circuit. Volvo being Volvo took it further with their 2-series cars in the 1970s and 1980s, where the front discs had four-pot calipers configured as two sets of two-pot calipers. Each braking circuit had one half of each front caliper and one rear caliper, so in the event of one half of t…

Yeah - but as we saw with the floormat/unintended acceleration, many people don't think of it in an emergency (all the fatalities could have been avoided by shifting into neutral in those cases, might have blown up the engine but wouldn't have crashed/killed).

Re: Never trust a system that seems to be working

#254

Post by xani_ »

electroly wrote: post #43

This is why 4-20 mA is a common signaling standard in industrial automation. 4 mA means zero and 20 mA means one. 0 mA means broken transmitter !

That's why in our monitoring we used nagios scheme + 1 (0 for invalid, 1 for ok, 2 for warning, 3 for crit, 4 for unknown)

Re: Never trust a system that seems to be working

#255

Post by jallmann »

electroly wrote: post #43

This is why 4-20 mA is a common signaling standard in industrial automation. 4 mA means zero and 20 mA means one. 0 mA means broken transmitter !

Also issue with golang (+ protobufs) where you can't distinguish a populated zero value from the default "not present" value.

Re: Never trust a system that seems to be working

#256

Post by Lukas_Skywalker »

samatman wrote: post #194
Lukas_Skywalker wrote: post #181

Earlier quoted context omitted.

Since this is HN, and I'm a pedant: reflexes can't be acquired, since they are not processed by the brain, but by the spinal cord, without involvement of the brain (e.g. pulling back the hand when touching a hot surface). What you're thinking of is called procedural memory, which helps you perform a task without being consciously aware of it (hitting a fast baseball, looking left/right when crossing a street).

This is quite far from being the case. Dr. Pavlov's seminal book is generally translated as Conditioned Reflexes . Saliva in response to a bell is a reflex, and it's an acquired one. Not falling flat on our face when we step forward is also reflexive, as is catching something thrown to us. Both are acquired through rather lengthy processes. There are many similar examples.

The term reflex has changed over the years.

Back in 1649, when Descartes formulated the concept of a reflex, it was used to describe lower animals, to support his notion that they were automata without a mind on their own. The word reflex originated from the "reflection" of the sensory input into a response. The physiological backgrounds were not yet known.

In the early 19th century, Hall narrowed the definition of a reflex to be a "involuntary action of a muscle or gland in response to the stimulation of a receptor neurone which does not depend on the existence of consciousness".

Sherrington, in 1904, narrowed the definition further, introducing the concept of the "reflex arc", a hardwired pathway between receptors and effector muscles.

Pavlov later did a strange thing and widened the definition, which is the source of some confusion. Nowadays, Pavlov's Conditioned Reflexes are mostly called Conditioned Responses, to avoid this exact confusion. NB: there are people arguing that conditioned is a mistranslation, and that it should mean conditional, which makes more sense in the context.

Pretty much every current publication uses the term "reflex" for involuntary, inborn responses, detected by receptors, transported to the spinal cord by afferent nerve fibers, processed there, and the motor signal sent through the efferent nerve fibers to the effector muscles. I only found the term "conditioned reflex" in papers discussing Pavlov's experiment.

Re: Never trust a system that seems to be working

#257

Post by xani_ »

bombcar wrote: post #127
acdha wrote: post #120

Earlier quoted context omitted.

That’s a great example of how you always have to design for a context.

Yeah, any design is going to be various trade-offs, and you have to understand them (and how they may relate to your mission) when determining what to do and what would be a bad decision. For example, cars have "fail open" brakes but have independent cylinders so that it is relatively hard to have all four wheels fail at the same time (older cars had single master cylinders) - and one of the tradeoffs is that people…

> For example, cars have "fail open" brakes but have independent cylinders so that it is relatively hard to have all four wheels fail at the same time (older cars had single master cylinders) - and one of the tradeoffs is that people want cars to get going immediately and not wait for brake cylinders to "charge up".

And emergency brake that's wholly separate circuit.

Re: Never trust a system that seems to be working

#258

Post by zelse »

city17 wrote: post #143
fknorangesite wrote: post #136

Earlier quoted context omitted.

If you're genuinely curious: > I have ADHD: it makes writing blogs hard but Twitter easy. So it gets quickly tiring that every time I'm posted there [to HN] that the comments immediately go "why isn't this a blog? Twitter is a bad site for this kind of writing and I hate it blarg" https://twitter.com/foone/status/1440695857699962893 This exact comment of yours is a prime example of why foone hates it when their tweet…

Thanks, that's interesting. I can see why it's easier for him to tweet in that case. But still doesn't change the fact that an article is easier to consume for the reader.

Foone is a them, not a him.

And yeah, you're right, it's definitely easier for the reader, but the author isn't required to make it easy for their audience -- if it was, Judith Butler wouldn't Judith...Butle and James Joyce wouldn't James Joyce. Foone writes tweets, 149k people have chosen to read their tweets. Personally, while I agree a blog'd be nice, I'm just glad foone makes their knowledge available.

Re: Never trust a system that seems to be working

#259

Post by Taywee »

hinkley wrote: post #202
csours wrote: post #35

If your code has side effects, it only ever seems to be working. ---- > the newbie says "aww, why isn't it working?" > the intermediate says "yay, it's working!" > the expert goes "hmm, why is it working?" I've also seen this as My thing isn't working and I change X and now I get error J instead of error K, so now I have to change X back because it's still not working. Where K is a "better" error than J, such as K =…

No news is bad news. I don’t like code that compiles cleanly or runs cleanly on the first try. The worst is when I know that code isn’t close to done yet. Without errors my list of actionable tasks is low. I know there are a certain number of problems, and if I can’t see any it’s because they’re invisible, not because I don’t have any.

I came here to say this exactly. There's nothing more stressful to me than when a lot of freshly-written C++ compiles without error or warning on the first try, and then seems to run without issues. I get the distinct feeling that there is a problem that I'm just not seeing yet.

Re: Never trust a system that seems to be working

#260

Post by xani_ »

hinkley wrote: post #202
csours wrote: post #35

If your code has side effects, it only ever seems to be working. ---- > the newbie says "aww, why isn't it working?" > the intermediate says "yay, it's working!" > the expert goes "hmm, why is it working?" I've also seen this as My thing isn't working and I change X and now I get error J instead of error K, so now I have to change X back because it's still not working. Where K is a "better" error than J, such as K =…

No news is bad news. I don’t like code that compiles cleanly or runs cleanly on the first try. The worst is when I know that code isn’t close to done yet. Without errors my list of actionable tasks is low. I know there are a certain number of problems, and if I can’t see any it’s because they’re invisible, not because I don’t have any.

Eh, that heavily depends on language. Some have better tooling to get most of the typical errors out before the compile.

That being said I'm always suspicious and start to fiddle with them if I see test + code pass on first time

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