
4-bit calculator made from cardboard and marbles - MaxLeiter
https://lapinozz.github.io/learning/2016/11/19/calculator-with-caordboard-and-marbles.html
======
ythn
Thought experiment: if sentient AI is possible with nothing more than
software, does that mean if you "load" the sentient AI program into a
"computer" made of cardboard and marbles, that the cardboard and marbles will
be self-aware?

~~~
zeroer
Yea, sure. What's so hard about that? XKCD made a comic about something
similar: [https://xkcd.com/505/](https://xkcd.com/505/).

It's unintuitive, sure, but that's just because of the enormous size of the
cardboard you'd need to do it. Human intuition is pretty bad outside of its
human-sized comfort zone.

~~~
ythn
> Yea, sure. What's so hard about that?

The hard part is coming to grips with consciousness merely being an abstract
or concrete system changing states and nothing more. If rocks on the ground
can be (slowly) self aware, then doesn't that mean everything in the universe
is self-aware?

For example, say I throw a bucket full of sand on the ground. Then, later, I
define an incredibly complex abstract computer, such that the sand falling out
of the bucket and shifting along the ground exactly represents a self-aware AI
within my defined computer going through its states. Does that mean as I was
pouring the the sand on the ground, the sand was momentarily self-aware?

~~~
__jal
> If rocks on the ground can be (slowly) self aware

If weird assemblages of water, carbon, calcium and trace minerals can be self-
aware, why not?

~~~
retina_sam
> If weird assemblages of water, carbon, calcium and trace minerals can be
> self-aware, why not?

Because humans (and indeed all life) have "spirits" which can think
independently of the body, and that's the true reason we are conscious/self-
aware. The body is merely a glove for the spirit. Before birth and after death
your spirit still exists and is self-aware (don't take my word for it; try it
out - when you die, think to yourself "wow, I'm still conscious without a
body!"). Spirits are created by God beings from intelligences (which is a
spiritual resource that can be neither created nor destroyed). Gods are
created by granting humans more knowledge and powers. The progression is this:
intelligence -> spirit -> human (body + spirit) -> God. However, not everyone
makes it to God status since Gods choose which humans are to be granted
further knowledge and power. And people that have been really bad can be
stripped of their body and spirit to have their intelligence recycled back
into the immutable pool.

Hence Strong AI is impossible since we aren't/don't know how to mine/utilize
intelligences (the immutable spiritual resource) like God does.

~~~
mcv
I understand the downvotes for retina_sam's comment for the number of unproven
ideas it asserts, but as unlikely as it seems in our materialistic view of the
universe, I think it's important to not lose sight of the possibility that
maybe there really is something special, something non-physical, about
awareness. It is really poorly understood, and I still have not seen an
adequate explanation for why I can perceive things and be aware of them.

"Awareness is an illusion", as proposed by some thinkers, certainly doesn't do
it for me, because there's still something that has to perceive that illusion.
It's got to be an emergent property of sufficiently complex logical
processing, but how does it emerge? What is it really? I feel like I'm still
missing a vital step.

~~~
hanspeter
The lack of an adequate explanation does not demand the need for a non-
physical explanation.

I think that because consciousness is part of the core understanding of
ourselves, we're drawn to a non-physical and spiritual explanation.

But as a phenomenon the conscious mind is not different than other observed
phenomenons.

The rational approach would therefore be to expect an explanation that can be
provided by our physical environment just as we do with any other unexplained
phenomenon we observe.

~~~
mcv
> But as a phenomenon the conscious mind is not different than other observed
> phenomenons.

Yes it is, because it's the phenomenon itself that does the observing. If not,
then what is it that does the observing?

~~~
shezi
I have never understood the argument that "observation" is something special
and that it must be taken into consideration. In fact, is it really the brain
that is observing a phenomenon or is it something else?

In the double slit experiment, it really isn't the brain, is it? It's the
screen you place some distance away from the slits, or the electron detector
if you place it in one slit only. The fact that "an outside observer" only
sees the pattern made by these detectors later and may reason about them is
entirely unnecessary to the experiment itself and to the collapse of the wave
function. If you leave the results of a double slit experiment lying
overnight, has the wave function not collapsed for longer? As such, the
"observer" in these experiments are devices, just like in most other
experiments.

Just as the infamous cat is an observer of a quantum system, for whom the wave
function has collapsed potentially much earlier than for an outside observer.
A wave function collapse is in that case much more of a statement of
information state than about the state of reality, which is the exact point of
quantum mechanics, in that there must be a distinction now between "observers"
(which my be single atoms, mind!) inside of the sphere of influence of an
event (whether that event may be bounded by physical barriers or a light cone
is irrelevant by the way). [Note that Schrödinger brought up the cat example
exactly to point out that the world does not exist in a blurry double-state
way even if unobserved.]

The same is true for most psychological observations, which get recorded by a
computer, by a pen or by an undergrad. The fact that someone else observes
these observations doesn't change the phenomenon in any reasonable way.

One more analogy: we now have computers that are entirely capable of
recording/observing phenomena by themselves, some of them internal to
themselves even, where we have no other way of recording such phenomenon. If
you run an A/B test on a web site, let it run for long enough, then look at
your analytics page and it says to accept one hypothesis with 99.99%
probability, then you have exactly the same situation as if you had done the
experiment through other people and publishing it as a paper. Except, of
course, no human mind has "observed" the phenomenon, neither directly nor
indirectly, until you opened the results page. So what it comes down to is
this: did the result exist before you read the results page? I would answer
yes.

All of this is a long way of saying that IMHO the observation of a phenomenon
does not change the phenomenon itself.

------
toomanybeersies
From the woodworking site posted a couple of days ago, Matthias Wandel made
one out of wood:

[http://woodgears.ca/marbleadd/index.html](http://woodgears.ca/marbleadd/index.html)

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ChuckMcM
People build these, and they are fun, and I'm surprised that they don't still
make and sell the Digicomp[1]. (yes I know some people have been doing limited
runs but it seems like there should be a persistent market for it)

[1] [https://en.wikipedia.org/wiki/Digi-
Comp_I](https://en.wikipedia.org/wiki/Digi-Comp_I)

~~~
fred256
Evil Mad Scientist makes and sells a Digi Comp II replica:
[http://shop.evilmadscientist.com/tinykitlist/375-dcii](http://shop.evilmadscientist.com/tinykitlist/375-dcii)

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ReedJessen
A literal example of race conditions ;)

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donquichotte
As one of the comments on the bottom of the page points out, Canadian
woodworker Mathias Wandel built a similar machine some time back:
[https://www.youtube.com/watch?v=GcDshWmhF4A](https://www.youtube.com/watch?v=GcDshWmhF4A)

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brownbat
These remind me of Dr. Nim, the unbeatable single-player board game from the
60s, which also used marbles to do binary math:

[https://www.youtube.com/watch?v=9KABcmczPdg](https://www.youtube.com/watch?v=9KABcmczPdg)

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sweetjesus
this calculator nicely illustrates an insight that I feel gets lost the way
most people learn and reteach some simple CS concepts:

"two's complement" is not a different system for arithmetic that includes a
"sign bit", it's just a different encoding or labelling of states which
happens to have a bit that reflects the sign. So, inputs to this calculator
can be said to go from 0-15, but more interestingly it can also add numbers in
the range -8 to +7 (and therefore, it can also subtract, though it can't
negate so you'd have to manually do that to your input by performing a
different encoding table lookup).

(edit: now I'm realizing you could negate by performing a two's complement
multiplication by -1, performed using this calculator via a sequence of 3
(shift+adds) of your input number to itself... that's correct at least up to
some fencepost)

And then by extension, you could test "what about treating the range as -10 to
+5", would that encoding succeed or break down? for starters, you would no
longer have a sign bit...

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bcgraham
This is a cool project. But when I was in school, if a classmate of mine came
in with this, it would have really rustled my jimmies. Some kids have much
better resources than other kids.

~~~
pavel_lishin
> _Some kids have much better resources than other kids_

Do you mean in the sense of "engineer parents who encourage this kind of
thing", or in the sense of "their own computer to research this on and time to
build it", or in some other sense?

I'm assuming you wouldn't have been envious of some kids' access to cardboard
and glue.

~~~
kkoomi
He didn't make the context he was referring to very clear, which is this:
"Then my sisters had a science activity where they had to present a science
project and I was helping them to choose a subject."

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moolcool
I won't be impressed till they run DOOM or the Linux kernel on it

~~~
mvindahl
Also, it should be self replicating.

And if it ever gains self-awareness and turns into Skynet, humanity could take
it down with a Zippo lighter.

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emmelaich
Reminds me of time that I was working as a clerk and doing CS part-time. It
was the early days of computers in the office and was asked how do these magic
machines work?

I replied that there was nothing special about electronics, computers could be
constructed out of many things. Water/pipes/valves. Ropes and pulleys [1][2]

They looked at me like I was an alien :-)

1\. [http://www.geek.com/geek-cetera/digital-computing-
demonstrat...](http://www.geek.com/geek-cetera/digital-computing-demonstrated-
with-ropes-pulleys-and-weights-1595808/) 2\. Nice April fool's joke (though
the principle is fine) [https://www.scientificamerican.com/article/computer-
recreati...](https://www.scientificamerican.com/article/computer-
recreations-1988-04/)

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qwertyuiop924
This is probably the coolest thing I have seen today.

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bbcbasic
Is the AND gate really an AND gate? It seems to be a counter. More like a
.skip(1) gate.

~~~
function_seven
It really is, with the caveat that a delay line is needed upstream to provide
the inputs in sequential time. But it satisfies the AND truth table:

    
    
        A  B  Y
        -  -  -
        0  0  0
        0  1  0
        1  0  0
        1  1  1

~~~
bogomipz
What does the delay line do?

~~~
function_seven
I think I may have used the wrong term. What I mean is that if you drop two
marbles into the contraption at the same time, they need to be serialized
before reaching this AND gate. A typical logic gate allows the signals to
arrive simultaneously, but this one doesn’t, so one of the signals (marbles)
needs to be held back while the other one goes first.

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gohrt
Wood version:
[https://www.youtube.com/watch?v=GcDshWmhF4A](https://www.youtube.com/watch?v=GcDshWmhF4A)

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e19293001
Here's a guy who made a 4-bit adder through water[0]. Creating a computer
through water seems to be really doable. I'd be interested to watch more
stuffs like this.

[0] -
[http://www.blikstein.com/paulo/projects/project_water.html](http://www.blikstein.com/paulo/projects/project_water.html)

~~~
commentzorro
Back in the late 80s or early 90s there was a group working on this a a backup
for military planes. The thought was the "water" (they used some oil like
fluid and machined metal blocks for the gates) wouldn't be susceptible to EM
pulses and could keep a plane in the air if hit with a pulse weapon.

I believe it was abandoned because solid state ICs grew way too quickly and
outpaced the ability of the liquid ICs to keep up.

~~~
ptaipale
"Liquid IC" as a pun on "solid state" is quite fun.

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Robin_f
This is awesome! Would be really cool if something like this would exist as a
2d animation so we can see what would happen with different kinds of input.

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mdonahoe
I suggest adding a binary-to-decimal decoder at the bottom to make demos more
exciting for people who can't read binary

I did that for a 4bit knex adder/subtractor

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z3t4
Given enough free time awesome stuff will happen.

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tmaly
Wow, that is pretty cool. It made me think of the book The Difference Engine.

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frostirosti
Now implement carry look ahead

~~~
posterboy
Calculators are a lot easier in unary, no carry-look-ahead needed either.

