Here's the thing. I hate stating the obvious. It really annoys me. On the other hand, obvious things are sometimes things that most need to be repeated. So I wrestle with myself and I finally decide that I should, because there is a shockingly large number of people out there who don't realize how obvious this is. See if you can learn something from this mock dialog.

Vendor: Good morning, is this Harry, the CTO*, I'm speaking to?
Client: Yes, how may I help you?
Vendor: Hey Harry, this is Steve from Microsoft. I would like to talk to you about Windows Vista.
Client: What's that?
Vendor: Why, it's the brand new version of our Windows operating system.
Client: Oh, that.
Vendor: I was wondering if I could interest you in our product.
Client: You know what, I don't think so, we are a very security sensitive company, and..
Vendor: But that's precisely the reason I'm calling, I would like to tell you how you can enhance your security with Windows Vista. You see, we've built the operating system with security in mind and it's the state of the art in operating systems.
Client: Hey, that sounds pretty exciting. So how does this work now, you ship us the source code and...
Vendor: No no, we don't distribute the source code.
Client: You don't?!?
Vendor: No, you see it's a trade secret. (my precious etc)
Client: You're kidding, right?
Vendor: No, really.
Client: So how do we know that it's actually secure if we can't see for ourselves? How do we know there isn't anything malicious in it?
Vendor: Well you'll just have to trust us.
*Harry hangs up*
Vendor: Hello? Harry?
*CTO - the highest placed person who makes technical decisions in a company.

How did it go? Did you get it? It was kind of a long thing, huh? Ok, stop racking your brains, I'll give you the answer: no source code, no security.

Here's how that works. It's simple economics, so try to keep up. If they give you the source code, then they put their cards on the table. You can see what the code does, and if it's doing something stupid (security hole) or nasty (like sending your data to back to the vendor), then you'll be able to check for this. Now you may say "I don't know how to check", and that's okay. But just by giving you the source code the vendor knows that you can see everything the code is doing. And if you find something nasty in there, they know you'll never trust them again. So it doesn't really matter if *you* don't know how to check, because there are others who do, and sooner or later someone will find the nasty code if it's in there. Thus, if the vendor gives you the source code, then he'll be a lot more careful about what's in there, because he's risking losing your trust and your business forever. That will keep him honest.

Is there then anything surprising about finding out that Microsoft is putting in backdoors in Windows? No, because how would you know it's there? You don't have the source code! In case you were wondering, the words "security" and "backdoor" are mutually exclusive.

So what have we learned today? Is there somehow we could summarize all this in just one sentence? There is: If you want security, ask for the source code. If you can't get the source code, you know that the vendor isn't taking security seriously.

I consider OLPC to be one of the most exciting initiatives of the last few years. When the idea was first circulated it was such an exciting call to arms to do something about the lack of education in poor regions of the world. And the project has produced what appears to be a pretty incredible product, the research of which is now recycled back into the general hardware industry, so it has brought advances that wouldn't otherwise have happened (now).

I recall pondering the real purpose of the project, asking what is going to be achieved with these laptops. The OLPC project had a very good answer to this. They said the laptops will promote learning in areas where school books are a luxury. Furthermore, the laptop itself is completely tweakable, you press a special key and the source code of the current program pops up. This will promote learning through tweaking and experimentation, so that eventually an industry can be built on these foundations, in regions where little industry exists today and where perhaps the potential for one (in terms of natural resources) is bleak. A beautiful dream, one that could change the world in big ways.

Now Negroponte has changed his tune. Visionary that he is, he failed to convince the clients of the value of free software. So now he's humming "forget open source, it's all about the kids!" while preparing to run Windows on the laptop. There is a new smoke screen being constructed:

Negroponte says that the organization is working to ensure that Sugar can run smoothly on Windows.

Riiiight, running Sugar on Windows. Tell me, what exactly is the value of running Windows with an all free software stack? It's completely useless, that's what. The whole value of Windows is as a platform, not merely as an operating system. People buy Windows to run Windows applications, not for Windows itself. Or are we actually buying that Egyptian officials are eager to purchase Windows licenses in order to run the free software suite?

Congratulations, Negroponte, you've just become a licensed Windows vendor. The kids will no doubt have fun clicking on the Start menu and playing Solitaire. There is a great deal to learn from that, just nothing about the operating system or the applications, you know, actual learning.

OLPC in its original form was about empowering the users, with Windows that capability is entirely destroyed. The fact you cannot mix learning with trade secrets should be blindly obvious to anyone. Open souce is important, but it's especially important when you want people to learn something.

Furthermore, learning doesn't happen in isolation. It's accelerated when it happens in a community of ideas and impulses that flow freely. Resigning OLPC president gets it when he says:

"What comes part and parcel with open source is a culture, and it's the culture that I'm interested in," he says. "It's a culture of expression and critique, sharing, collaboration, appropriation." And this culture can and should spill into classrooms, he says.

Most people are reasonably discreet by nature. They don't feel an urge to flaunt their personality or draw attention to themselves that often. It's a fact of life that we live in an unfriendly world, amongst aggressive peers. If you stick your neck out more then you'll have to stand up for yourself more. Thus most people develop a (healthy? at least in terms of survival) tendency to not advertise themselves excessively, especially not facts they suspect their peers will consider weaknesses. And so when they find themselves in a classroom with 24 peers, they feel somewhat less than eager to declare ignorance about the current topic. Teachers know this, and they think it's unfortunate that the fear of embarrassment keeps people from learning. And this is when they declare that: There is no such thing as a stupid question!

This is a well meaning encouragement to dare to admit that you're ignorant, because in this room you're allowed to be. Unfortunately, it's also a misleading statement. If you've ever taken a class with a person who wasn't shy, but *did* ask a lot of stupid questions, you already know that a) there *is* such a thing as a stupid question and b) it is ill advised to keep asking them. A person who is either particularly ignorant or exceptionally obtuse is a real disruption to the thought process among people who can follow the material. Just in the same way that you wouldn't want someone to interrupt a movie every 5 minutes and spend 2 minutes explaining what just happened on the screen, it really destroys the flow.

The teacher is probably more tolerant of stupid questions than your peers are, but there is a limit to how much time can be spent explaining obvious things to an ignoramus, because after all the mission is to get through all of today's material. So stupid questions are obviously not appropriate in large quantities, whatever the commercial says.

Interestingly, the expression isn't it's okay to ask stupid questions, so no allowance is made for those questions at all. On the contrary, it redefines all questions to be of the not-stupid nature. Perhaps we should call them "smart questions". The not-stupid reader will notice that the result between that and admitting stupid questions is ultimately the same. Whether you're allowed to ask stupid questions, or you're not allowed to, but there are not stupid questions, it is permission granted to ask all questions. And the strange twist is just a little morale boost for you, an encouragement. We allow stupid questions, but your questions aren't stupid anyway, so don't worry about that. *wink*

As bogus as the expression is, is there any truth to it at all? It defines "stupid questions", some category that apparently must have been discovered by someone. If stupid questions form a subset of all questions, there must be another category that isn't stupid. So is it actually true that it's impossible to distinguish a presumably stupid question from a smart question? Why, that too is completely untrue, anyone who took the class with that stupid-questions-asker knows this.

So we know that a) stupid questions exist and b) you shouldn't be asking them. But here's the problem: how do you know if your question is stupid?

It seems to me that there is no general answer. If we take the literal definition of the word "stupid" we find:

characterized by or proceeding from mental dullness; foolish; senseless: a stupid question.

However, none of these assessments - dullness, foolishness, senselessness - are absolute terms. They take on meaning in context, and only then. So in other words, if you are a globally renowned expert in some field and you receive questions from people all around the world, people whose background you know nothing about, and with whom you've never interacted before, then none of those questions, no matter how elementary, can be stupid. Because it's impossible to infer "mental dullness", or "foolishness", or "senselessness" based on one question.

Wherever you have a congregation of two persons or more the accepted standard of discourse on any topic that comes up is decided within a few minutes, as soon as the participants negotiate an acceptable place to set the bar. Just how this happens is too complicated to cover here, but it's influenced by things like how socially dominant the various participants are, what they stand to win or lose by admitting to competence or ignorance and so on. However, once that standard has been informally negotiated, any questions visibly below the standard will be perceived as stupid.

Although the audience makes an instant determination about a question being asked, this isn't actually a correct assessment. Broadly speaking (although this departs somewhat from the dictionary definition), stupid questions can be divided into two categories.

First, there are ignorant questions, which betray a lack of competence about the topic. This is just an indication that the person doesn't have the same background as everyone else. This is actually less of a failing for the person in question, because you can't really blame someone for not knowing something they haven't had the opportunity to learn, can you? But it's still very disruptive to everyone else.

Second, there are questions that are by definition stupid. "Mental dullness" would be a failing to make the right deductions based on the known facts. So a prior fact "this chair is heavy", combined with a new fact "heavy things hurt when dropped on your foot" would make the question "what happens if I drop this chair on my foot" a stupid question. It would also be a foolish idea, which seems to me as being "mental dullness" in a case where the outcome is unfavorable to you personally. But you could also ask a different question. "But what if this happened on a Tuesday, would it still hurt?" That question makes no sense. It seems to me that "senseless" questions stem from a false conclusion somewhere in deduction, ie. that the day of the week has an impact on your physiological responses.

While questions due to ignorance are an obvious waste of time (depending on the degree of ignorance), questions due to "mental dullness" are socially accepted to a point. The real problem is that the assessment isn't accurate.

To determine whether a person is:

lacking ordinary quickness and keenness of mind

we would have to compare his performance to that of another person. In other words, given the same facts, will the dull person fail to make the deduction while the other succeeds? If so, a question that betrays the absence of this deduction would correctly be described as stupid.

But how to conduct such an experiment? People gather in a classroom from all corners of the city (just to keep it simple). If they attended different schools they would not have had the same curriculum. But even two persons with the exact same schooling does not guarantee that they will have absorbed the same facts. Perhaps one was paying attention while the other didn't, perhaps one was gone that day, perhaps one remembers this fact and the other doesn't, perhaps one never understood it while the other did. Memory tests conducted with groups of participants show that a 30 minute exposure to the same words, images etc produces vastly different recollections of what was seen.

So if we cannot stage such an experiment then we cannot infer dullness of mind, and hence the determination of the stupid question is undecided.

So it cannot be decided from the outside, but the person cannot decide this either. You can ask yourself the question "if there some basic fact that makes this question stupid that I'm not aware of?". If so, it will be judged a stupid question, but it's not stupid based on *your* known facts. And it's only after you've understood the topic that you can determine if it was stupid. If it turns out you were missing necessary information, then it wasn't stupid. If you weren't missing anything, then it would seem you mind was "dull". However, if you have a "dull mind" to begin with, then perhaps you see no anomaly in your performance that day.

The senseless question is an interesting case, because it originates from a false conclusion. What are we to make of this? Is it because you misinterpreted a fact and thus made a wrong turn, or did you have all the facts straight, but still somehow managed to deduce the wrong thing? That brings up the question of whether the mind is capable of making an incorrect deduction like that. Or whether you're guaranteed, having all the right facts, to produce the right answer. That is a common assumption we make when debating with people. We think just as long as we straighted out their warped world view, we can get them thinking straight.

So you can't tell if the question is stupid, and the audience doesn't know if it's stupid, even if it's obvious to them. Maybe that's why someone got really depressed and went into denial, postulating that there are no stupid questions. I guess that means there are no foolish or senseless questions.

If you've been dealing with files for a while you will have noticed that there is a slight semantic gap between how humans see files and how computers do. If you've ever seen a file list like this you know what I mean:

Lecture10.pdf
Lecture11.pdf
Lecture12.pdf
Lecture1.pdf
Lecture2.pdf
...

Numbering these files was done in good faith, and a user understands what it means, but the computer doesn't get it. Sorting in dictionary order produces the wrong order as far as the user is concerned. The reason is that the digits in these filenames are not treated and compared as integers, merely as strings. (Actually, . comes before 0 in ASCII, what's going on here?)

While we're not expecting our computers to wisen up about this anytime soon, there is the obvious fix:

Lecture01.pdf
Lecture02.pdf
...
Lecture10.pdf
Lecture11.pdf
Lecture12.pdf

You've probably done this by hand once or twice, while cursing.

On the upshot, this is very easy to fix with a few lines of code:

#!/usr/bin/env python
#
# Author: Martin Matusiak <numerodix@gmail.com>
# Licensed under the GNU Public License, version 3.
#
# revision 1 - support multiple digit runs in filenames

import os, string, glob, re, sys

def renseq():
    if (len(sys.argv) != 2):
        print "Usage:\t" + sys.argv[0] + " <num_digits>"
    else:
        ren_seq_files(sys.argv[1])


def ren_seq_files(num_digits):
    files = glob.glob("*")
    for filename in files:
        m = re.search("(.*)(\..*)", filename)
        ext = ""
        if m: (filename, ext) = m.groups()

        digit_runs = re.finditer("([0-9]+)", filename)
        spans = [m.span() for m in digit_runs if digit_runs]
        if spans:
            spans.reverse()
            arr = list(filename)
            for (s, e) in spans:
                arr[s:e] = string.zfill(str( int(filename[s:e]) ), int(num_digits))
            os.rename(filename+ext, "".join(arr)+ext)
    


if __name__ == "__main__":
    renseq()

This works on all the files in the current directory. Pass an integer to renseq.py and it will change all the numbers in a filename (if there are any) to the same numbers, padded with zeros if they have fewer digits than the amount you want. So on the example

renseq.py 2

will turn the first list into the second list.

If say, there are filenames with numbers of three digits and you pass 2 to renseq.py, the numbers will be preserved (so it's not a destructive rename), you'll just revert to your incorrect ordering as it was in the beginning.

renseq.py will rewrite all the numbers in a filename, but not the extension. So mp3 won't become mp03. ;)