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Ask HN: Teach me something new

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Re: Ask HN: Teach me something new

#611

Post by SemanticStrengh »

kaba0 wrote: post #595
SemanticStrengh wrote: post #553

Earlier quoted context omitted.

Re-read my sentence, yes the cerebellum is part of the CNS and so is the spinal cord. Is the spinal cord part of the brain? Why not. What I meant is what people generally denote and imagine when we speak about the brain, is actually the cerebrum https://www.cancer.gov/publications/dictionaries/cancer-term... The cerebellum, pons, etc are distinct extensions.

The brain/spinal coord is commonly divided at the start of the brain stem. By all accounts, the cerebellum is part of the brain.

It is part of the brain but not in the mind of the layman which is what I meant. If you asked to someone wether the vast majority of our neurons are located in the cerebrum (not the cerebellum) they would say "of course".

Re: Ask HN: Teach me something new

#612

Post by jonwest »

causality0 wrote: post #455

Put your non-dominant thumb in the palm of your dominant hand and squeeze it as hard as you can for thirty seconds. Afterwards your gag reflex will be suppressed for about a minute. Enjoy touching your own uvula.

Some of these posts have been incredibly interesting but this is the first one to be both bizarre but also immediately permanently learned. What the hell? What else is this weird body capable of haha

Re: Ask HN: Teach me something new

#613

Post by mdp2021 »

mikelevins wrote: post #599
mdp2021 wrote: post #543

Earlier quoted context omitted.

Sure, but those colours still «are electromagnetic frequencies». The poster stated that some colours are not.

If the colors were the same thing as the electromagnetic frequencies, then the same electromagnetic frequencies would be the same colors, by definition. They aren't. For example, put a card of color A in front of a background of color B; now move it in front of a different background of color C. You will experience color A as being a different color (especially if colors A, B, and C are chosen to maximze the effect).…

> If the colors were the same thing as

Oh, nobody said they overlap.

The original post claimed that «Colors don't exist outside of your brain»: such statement, while true, is false, as its negation is true (we have mentioned paraconsistency in this very page): "colours" do exist outside your brain, as their nature also is, in a way, being electromagnetic phenomena, function of frequencies.

While such ontological property is pretty common, it is just summoned with some force when someone claims "[fuzzy] is [strict]".

> Thus, electromagnetic spectrum is "out there", but color is "in here"

Of course. That just depends on what you want colour to be. If you put it conceptually near "electromagnetic spectrum", then the distinction emerges.

Re: Ask HN: Teach me something new

#614

Post by jonwest »

tallytarik wrote: post #187
silisili wrote: post #63

I'm going to go a bit random...get a styptic pencil! Nobody I've met even knows what they are. I came across them years ago in the shaving section, and was blown away by their utility. They are solid pieces of some saltlike material that are super effective at stopping bleeding. We don't even have bandaids in our house anymore, the pencils are way more useful.

Roll-on antiperspirant is also great at stopping bleeding from shaving cuts. (Spray antiperspirant might be, too, but spraying myself in the face has never sounded particularly appealing) It’s not designed for this purpose, and you’re putting this substance on an open wound, so try at your own risk.

That’s because styptic pencils are generally aluminum based, as is anti-perspirant.

Re: Ask HN: Teach me something new

#615

Post by SemanticStrengh »

kaba0 wrote: post #596
SemanticStrengh wrote: post #179

Earlier quoted context omitted.

> There have been cases studies of people with a fully ablated cerebellum, and they can still walk, just a bit unsteadily. ? I had heard the cerebellum is responsible for predicting the next token in a sentence (reminiscent of language models) but you're saying language is not impaired without a cerebellum?

The axons are just as important as the neurons. While neural networks are not good analogues of the real thing, one can imagine that no matter the neurons, without weights between them it would be utterly useless. The cerebrum is chock full of axons.

> The axons are just as important as the neurons

We don't know about that.

> without weights between them it We don't know where are located the weights but yes probably. We know for sure that individual neurons and axons do not reduce to a single floating point though. They have action potential memory and many dynamic modulators. Basically I believe the idea that neurons are mostly doing linear regression (which is what neural networks are) is very broken. I have read papers about neural coding and neurons are able to encode information in the spike timing frequency and in the strength (weight) but non of those two mechanisms even begin to explain how the system works.

Anyway to answer your comment you have a tentative point but mostly unknown. It is unknown how much percent of human axons are in the cerebrum vs the cerebellum. I would be surprised if the cerebellum would have less since I expect some kind of neuron/axon proportionality. Especially since the main neuron type in the cerebellum are highly branchial.

Re: Ask HN: Teach me something new

#616

Post by schoen »

tazjin wrote: post #363
schoen wrote: post #132

In the 1800s, scholars who knew a lot of languages (including, often, several modern and ancient European languages, and increasingly also Sanskrit) started to notice some amazing patterns about similarities in words among all of these languages, including languages from very far apart and that had no visible connection at all from the point of view of their present-day speakers. As these patterns were explored, they…

I've always found it interesting that some words are constructed the same across many languages. For example, response: responsibility in - English (well) - Russian (ответ : ответственность) - German (Antwort : Verantwortung) - Scandinavian (svar : ansvar) There's likely more! Even though the modern words have diverged completely, the concept behind the construct is the same.

Note that a large number of these examples in European languages are calques

https://en.wikipedia.org/wiki/Calque

In these cases, people who knew both languages consciously adopted the structure of a foreign word by translating its components (morphemes). For example, German has a lot of calques from Latin compounds.

That is to say that it's not always a coincidence or an indication that people inherently think of the concept in the same way; sometimes it's an indication that people thought a foreign word for a concept was awesome, and wanted to borrow it by translating it literally.

Re: Ask HN: Teach me something new

#617

Post by Cosi1125 »

tazjin wrote: post #363
schoen wrote: post #132

In the 1800s, scholars who knew a lot of languages (including, often, several modern and ancient European languages, and increasingly also Sanskrit) started to notice some amazing patterns about similarities in words among all of these languages, including languages from very far apart and that had no visible connection at all from the point of view of their present-day speakers. As these patterns were explored, they…

I've always found it interesting that some words are constructed the same across many languages. For example, response: responsibility in - English (well) - Russian (ответ : ответственность) - German (Antwort : Verantwortung) - Scandinavian (svar : ansvar) There's likely more! Even though the modern words have diverged completely, the concept behind the construct is the same.

Polish: odpowiedź : odpowiedzialność

Re: Ask HN: Teach me something new

#618

Post by schoen »

yobbo wrote: post #337
schoen wrote: post #132

In the 1800s, scholars who knew a lot of languages (including, often, several modern and ancient European languages, and increasingly also Sanskrit) started to notice some amazing patterns about similarities in words among all of these languages, including languages from very far apart and that had no visible connection at all from the point of view of their present-day speakers. As these patterns were explored, they…

The swedish/scandinavian word for human "människa" has three syllables (norwegian "menneske" sounds more like two syllables) as opposed to german "mensch". It sounds suspiciously similar to the sanskrit word "manusha" which apparently also means human.

I suspect, without having researched it, that människa and mensch are direct cognates where vowels have been inserted for various reasons.

It's not unusual that an affix can have a form with a vowel that gets lost or added, or that cognates can have different morphemes in addition to their shared morphemes. (For the latter case, when writing about Grimm's Law above, I re-learned that although "hundred" is cognate with "centum", the "red" part is a separate Germanic morpheme meaning 'count'. For that matter, the "um" part is a separate Latin morpheme that is a neuter noun ending.)

Re: Ask HN: Teach me something new

#619

Post by schoen »

senjin wrote: post #515
schoen wrote: post #139

Earlier quoted context omitted.

Wow, I did not know that! I would have referred to this using !$, which is one of the Bourne shell history substitutions. Like $ mkdir awesome $ cd !$ (The "!" has the connotation "history" in the shell, while the "$" has the connotation "last", as in regular expressions.) An advantage of the way you mentioned is that you could actually see the history item displayed on the command line before running the command!

I use !$ multiple times every day but you just helped me make the connection to try !^ for the first argument and I think I'm going to start using that as well. Thanks!

There is also "!!" for the entire prior command line. Someone elsewhere in this thread mentioned the usefulness of

  sudo !!
for "run the entire previous command under sudo".

Another example could be

  echo "!!" > myscript
for "save the previous command into the file myscript".

Re: Ask HN: Teach me something new

#620

Post by tomcam »

mikelevins wrote: post #424
tomcam wrote: post #421

Earlier quoted context omitted.

Well that’s great to hear! May it be your last.

I'm sort of hoping I'll get another chance to try it. Obviously, I'd prefer another scotoma without the rest of the migraine, though!

You a mad lad, brah
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