A List of One.

[Toby Inkster]

the idea of empty lists doesn't seem logical at all to language or
document mark-up.

Does make sense to me.

<p>My current to do list is:</p>
<ul></ul>

conveys more meaning than:

<p>My current to do list is:</p>

which merely seems like an incomplete statement.

 

[dorayme]

in maths, two negatives make a positive, wheras in language
(English at least) two negatives are just emphatically negative. "I don't
know nothing about it".

This is quite misleading and vague I am afraid. In maths,
sometimes two negatives make a negative:

(-2) + (-2) = -4

And in language, there are many examples of two negatives
"making" a positive, not least of which is:

2 + 2 = 4

which is not a non-English statement nor is it a non-
mathematical one.

The other difference between the idea of a list and a set, is that lists
imply an order, even an unordered list <ul> still retains that quality.

This is because ordinary language is (usefully) vague. But you
need to be a bit careful. Two lists can contains the same items
but in different orders yet be the same: imagine a mother gives
her child a list of things to buy, he loses it and she writes the
list out again. It is the same list for all intents and purposes,
the fact that a couple of items are in a different order is not
important enough to make it an essentially different list. If 500
people list their equal favourite 3 films and all write the same
films, their lists are the same.

It all depends on context. The notion of a ul and an ol is a
refinement, a clarification, a canonical logical representation
of the possibilities in this area. In maths there is the notion
of the ordered pair, it is a set or class notion and has order
built into its very meaning.

 

[dorayme]

because being a list, sequence is important.

This is quite not quite so, davmon. I have outlined why in
another reply...

 

[dorayme]

In computer-related languages, the first thing is usually the "0" thing.
Javascript, for example, numbers the initial item in the images array (-and
all arrays) "0". It can be argued that a zero item

Using 0-9 is just a way of counting (saves having to use "10"), I
would not draw too many deep conclusions from it Boji.

 

[dorayme]

<ul>
<li>Oak.</li>
</ul>

convey to you that

<p>Oak.</p>

doesn't?

That there is just one left in the landscape of which the
environmental website is all about. The former brings the point
home in the way that the paler latter does not.

 

[Jonathan N. Little]

This is quite misleading and vague I am afraid. In maths,
sometimes two negatives make a negative:

(-2) + (-2) = -4

And sometimes can result in a positive:
(-2) * (-2) = 4

;-)

 

[dorayme]

And sometimes can result in a positive:
(-2) * (-2) = 4

;-)

Yes, indeed, this is usually how the word "sometimes" works. But
not always! Some, like an empty class, can have zero instances.

 

[Jose]

Does context change maths as it does language, so that

1+1 != 2 somewhere in the universe?

Early pentiums.

Consider a script which generates an HTML page listing bus riders. Each
time somebody swipes a farecard to enter or exit, the list is updated.
One day halfway through the run, the last passenger exits. Three
stops later, a passenger is waiting, and a stop after that five
passengers are waiting for the bus.

What happens to the bus, and to the unordered list of passengers, in the
interim. Does it simply cease to exist?

As Descartes might say, "I think not".

Jose

 

[Adrienne Boswell]

I don't know!

What don't you know that you don't know? In other words, there are things
that you don't know that you don't know.

 

[Neredbojias]

To further the education of mankind, dorayme

Using 0-9 is just a way of counting (saves having to use "10"), I
would not draw too many deep conclusions from it Boji.

My conclusions are seldom as deep as my confusion.

So, you are saying that this is just another geek hack which tends to cause
trouble for anyone in the real world? -Might have known. I'm a little
peeved right now 'cause I just ran across another Mozilla bug that foiled
my most honorable petard. Did you ever think that so-called smart people
are stupid people with exceptional focus? It's true...

 

[Neredbojias]

Early pentiums.

Consider a script which generates an HTML page listing bus riders. Each
time somebody swipes a farecard to enter or exit, the list is updated.
One day halfway through the run, the last passenger exits. Three
stops later, a passenger is waiting, and a stop after that five
passengers are waiting for the bus.

What happens to the bus, and to the unordered list of passengers, in the
interim. Does it simply cease to exist?

As Descartes might say, "I think not".

In Logic they teach that an empty set is still a real and valid set; it is
not null. Some philosopher or other stated that if something _could_
affect reality (potentially), it existed.

 

[PeterMcC]

Davémon" <"davémon wrote in

PeterMcC arranged shapes to form:


Among the people who use the phrase, always.

"You were rather quiet."
"Yes, but I didn't say nothing."

Or how about litotes as a double negative making a positive?

"The case is not without merit."

I don't know!

I don't know nothing

 

[PeterMcC]

Adrienne Boswell wrote in

What don't you know that you don't know? In other words, there are
things that you don't know that you don't know.

Oh, I don't know...

 

[Toby Inkster]

In computer-related languages, the first thing is usually the "0" thing.
Javascript, for example, numbers the initial item in the images array (-and
all arrays) "0".

Ususally this is for historical and practical purposes.

An array is often represented in memory as a single number that points to
a location in memory. So the array "myvar[]" might refer to address "1000"
in memory.

If we want to retrieve the first item of the array, we can find it at
memory address 1000. If we want to retrieve the second item in the array,
it's at address 1001; the third item, at 1002; and so on.

myvar[0] stored at 1000+0
myvar[1] stored at 1000+1
myvar[2] stored at 1000+2
etc

So retrieving an array item would be implemented internally by the
programming language like this:

function retrieve_item (array, index)
{
data_width = size_of(data_type_of(array));
address = address_of(array) + (index * data_width);
return retrieve_bytes(index, data_width);
}

Anyway, that's how arrays were implemented in many older programming
languages, and still are in lower-level languages like C. Modern,
higher-level languages don't tend to implement arrays like this, but
retain 0-based indexes because that's what programmers are used to.

 

[Neredbojias]

To further the education of mankind, Toby Inkster

In computer-related languages, the first thing is usually the "0"
thing. Javascript, for example, numbers the initial item in the
images array (-and all arrays) "0".

Ususally this is for historical and practical purposes.

An array is often represented in memory as a single number that points
to a location in memory. So the array "myvar[]" might refer to address
"1000" in memory.

If we want to retrieve the first item of the array, we can find it at
memory address 1000. If we want to retrieve the second item in the
array, it's at address 1001; the third item, at 1002; and so on.

myvar[0] stored at 1000+0
myvar[1] stored at 1000+1
myvar[2] stored at 1000+2
etc

So retrieving an array item would be implemented internally by the
programming language like this:

function retrieve_item (array, index)
{
data_width = size_of(data_type_of(array));
address = address_of(array) + (index * data_width);
return retrieve_bytes(index, data_width);
}

Anyway, that's how arrays were implemented in many older programming
languages, and still are in lower-level languages like C. Modern,
higher-level languages don't tend to implement arrays like this, but
retain 0-based indexes because that's what programmers are used to.

As I said - a sop to the geeks. But it's interesting that by starting
storage at some "round" number such as 1000, one leaves 999 memory
addresses before it. Further, elemental computer communication is done
in binary which may be "up-verted" to hexadecimal, neither of which holds
decimal 1000 to be a "round" number. In other words, the procedure is
just a sloppy programming technique.

In spite of all this, yes, "0" is not actually a value like any normal
ordinal number. However, you must have zero *something*. You can't have
zero *nothing*. I believe that's why the geek-boys call "null" a special
value. It doesn't say "I don't have any of these"; it says "there is no
'these' to begin with."

 

[Jose]

Did you ever think that so-called smart people

are stupid people with exceptional focus?

Snarfed for my quote list.

Jose

 

[Neredbojias]

Snarfed for my quote list.

Hehe, here's one of my favorite narratives related to the subject extant.

A helicopter was flying around above Seattle yesterday when an electrical
malfunction disabled all of the aircraft's electronic navigation and
communications equipment. Due to the clouds and haze, the pilot could not
determine the helicopter's position and course to steer to the
airport. The pilot saw a tall building, flew toward it, circled, drew a
hand-written sign, and held it in the helicopter's window. The pilot's sign
read "WHERE AM I?" in large letters. People in the tall building quickly
responded to the aircraft, drew a large sign, and held it in a building
window. Their sign read "YOU ARE IN A HELICOPTER." The pilot smiled, waved,
looked at his map, determined the course to steer to SEATAC
airport, and landed safely. After they were on the ground, the copilot
asked the pilot how the "YOU ARE IN A HELICOPTER" sign helped
determine their position. The pilot responded "I knew that had to be the
MICROSOFT building because, similar to their help-lines, they gave
me a technically correct but completely useless answer."

 

[Toby Inkster]

As I said - a sop to the geeks. But it's interesting that by starting
storage at some "round" number such as 1000, one leaves 999 memory
addresses before it.

1000 was just for the purposes of illustration. The array could equally
be stored at address 0, or 6, or 21890 -- it's not a matter for the
programmer to worry unduly about -- compilers tend to do a pretty good job
of slotting tonnes of integers, strings, arrays, etc into memory with very
little free space in between.

 

[dorayme]

... In other words, there are things
that you don't know that you don't know.

"there are things that you do not know...."

Like that there is an island called Tasmania.

And further, you are suggesting, you may not know that you do not
know that there is an island called Tasmania.

And when shall we stop? Is it then the case that you do not know
that you do not know that you do not know...

In other words, is ignorance something quite bottomless?

Why depress us all, Adrienne? It is more comforting to think
there is some limit, a floor to our mortal deficiencies.

 

[dorayme]

Some philosopher or other stated that if something _could_
affect reality (potentially), it existed.

If something exists that can have a causal effect then,
naturally, it exists. However, if you are admiring some
philosopher for suggesting that something that does not exist can
have a causal effect, you better be careful.

The absence of money in your pocket can get you into real trouble
on a bus when the conductor comes to collect the fare.

Its non-existence, however, is not really having a causal effect.
There is no money to do this. What is having an effect is your
failure to pay the conductor. That failure is plain to see.
Nothing non-existent or potential about that.

On the other hand you might want to say that the mere possibility
of winning the lottery is cause for you to buy a ticket. After
the draw, you don't win but you might have. The potentiality had
a causal effect. But you need to be careful before swallowing
this whole: what caused you to buy the ticket may just have been
you thinking (rightly) that you could have won. You thinking this
is a brain process that exists and can obviously have effects.
This is quite different to the mere possibility causing things.
Remember, smart people tend not to buys lottery tickets, it is a
bad bet.