Surfing the net will give you quite a breadth of knowledge, but it won’t be very deep. I know this is true for me.

Someone would do very well for themselves if they found out how to impart deep knowledge while still giving the user the quick satisfaction that shallow, new knowledge can bring.

Maybe the socratic method?

Just a thought.

I know, I know, I haven’t posted in a while. See, I have a problem. It has been haunting me for my whole life, really. I tend to procrastinate because of loose ends. For example, my blogging internal dialog goes like:

“Ah, I want to write about some certain topic. But crap, I still haven’t found a syntax highlighter solution for the free WordPress accounts, and I can’t find any free blogs that support it either.”

And then, my brain freezes. If I have an unsolved problem that is vaguely related to the thought, I drop everything. Just something I have to overcome.

However, I HAVE found a solution to my problems — github blogs. So, http://notyouravgjoel.github.com will now be my blog for any CS/math topics, but I’ll keep posting up here for the more random things, such as essays, links, and ideas on living a good life.

I often encounter some issue or another in which I would like to post, but then I realize that it might be misconstrued as saying something bad about me.

This reminds me of the myriads of articles I’ve seen which say that online information has been increasingly accessed by interviewers, trying to find some inside information on their employees. Thus, don’t post those random pictures of doing something to be looked down upon.

I think this is all silly. Understandably, some things nobody would like as a personality trait in an employee. But, aren’t we all human? Are we all perfectly ideal drones?

Of course, there is the thought mentioned by Steev that his having tattoos, piercings, etc only serves to help “weed-out” places that he, himself, would not want to work for. So, you’ll have that.

In my personal life, I am fairly reserved. I really don’t worry about details from my personal life being known on the internet (for example, you’ll never see pictures of me drinking from a keg on the internet, because it doesn’t happen), however I AM concerned that a future employer might think that libertarians are crazy folk, and thus not hire me, or one of my other views are out-of-sync with their company’s ideals.

Anyone else worried about this?

I was young (If I had to guess, twelve or thirteen), sitting in the musty-smelling spare room at my grandmother’s house. PBS was showing Scientific American Frontiers [1]. I loved that show. The TV showed a bald headed man with a bushy mustache, and began to tell about this amazing thing he discovered: If you lower the normal calorie intake of mouse while feeding it extremely nutritious food, you can double it’s lifetime. And not just it’s lifetime. It’s healthy, vital years. This extraordinary mouse will spend more time being healthy and vibrant as that of other, more normally fed mice. We then learn that this has worked just not in mice, but in every animal it has been tested on. Yes. Let that sink in.

And then, SAF was over, and I was still my young self, intrigued but unable to do much of anything about it. I really didn’t have any access to the internet at the time, and thus had no easy way to do research.

Fast forward a few years, and I’m sitting on the floor in the Health foods section of the Carnegie Library, looking at books, and my eye catches on “The 120 Year Diet”. I begin to flip. Wow, this is the same guy talking about the same thing, but it has more validation, more proofs, and more evidence.

There is some trouble with the idea, however, and I admit this readily. Calorie restriction has not been proven to work on humans. There are studies going on about rhesus monkeys, and the results seem promising. But who knows? There is nothing sure in life, and so much hand-waving goes on in biology that we humans may not benefit by calorie restriction.

I am going to be starting this. I’ve been thinking about it for a while, and I believe that it would not, at least, harm me. And at least the advice is sound: who would disagree that a low calorie, high nutrition diet is healthy?

[1] You know what I mean by Scientific American Frontiers: the great show that the Pittsburgh PBS station never played. WHY NOT? Why did I have to go to West Virginia to see shows like Scientific American Frontiers or Nova, and all our PBS ever seems to play are obscure dry British shows and Sesame Street. Hint: People who watch Sesame Street don’t have money. They’re children. The parents who most use Sesame Street (as a babysitter) also don’t have money. And, even if they did have some to spare, why would you believe that they’d feel an altruistic urge to donate to you, PBS? No, because they would be raising their children. Bah.

I used to occasionally watch music videos with the sound off. I think this is one of the funniest ones to do it with — dancing looks pretty insane whenever you don’t have the cues from the music.

So, sit back for a few minutes, turn your sound off, and enjoy.

PS, if you think of any other great videos to do this with, do share.

I have a problem. I am about to graduate with a degree in CS, but every programmer position I’ve ever had has caused me to cringe. It wasn’t this way when I first started at University. I loved almost any programming, and I was eager to learn everything.

To any programming language, your specific advantage is better implemented as a Scheme DSL/macro.

My point being, I don’t think I want to program, at least for anyone else. I can’t shake the steady “You’re doing it wrong!” feelings.

In lieu of that, I think the best job a person could have is some sort of writer/essayist, especially if you are independent. This writer gets to spend his day researching and thinking about what he is currently choosing, and then trying to thoughtfully convey his thoughts and research.

I can’t imagine a better job.

(This post has also been moved to the page “Conceptual Purity”)

It is the middle ages, the time of the crusades, and a pious a christian knight is being told to war. The pope wants to take back the holy land from the heathen muslims. He knows that god works through the pope, and thus the murder must be acceptable to god.

However, he knows that the bible says not to murder in any case, and he knows that the bible is god’s word. This tells him that murder is unacceptable to god.

He has a case of murder is acceptable to god, and murder not being acceptable to god, a contradiction.

An American legislator is being pressured by the majority of the population to enact new government-expanding legislation that allows domestic spying. Since America is founded on democratic values, the will of the people should be upheld, and thus this legislation should be enacted.

However, another central tenant is freedom and respect for privacy. This legislation invades privacy and limits freedom, and thus this legislation should not be enacted.

Our legislator must now decide to either respect freedom or respect democracy; he cannot do both.

These examples show how “uncleanliness” in a concept can lead to ruin. Both people have guiding principles, but in the mentioned areas, these principles conflict. The legislator is in an especially problematic spot, because if he erodes freedom, people may tend to value their freedom less, seeing that they haven’t been drug from their homes due to the domestic spying (meanwhile, those who have been are unable to speak out).

I believe that one of the most important concepts in life is conceptual purity. Concepts are pure when they are absent of logical contradictions. This philosophical concept gives helps rid us of problems and conceptual baggage, as a person or a society. There are many questions that need answering in life, and going about answering them in the wrong way can only lead to more problems.

Thus, we have the definition of conceptual purity:

A concept is pure when a logical contradiction cannot be reached using its principles.

I probably have about a dozen or so interesting blog posts that are almost written, waiting to be published. Typically, they are partially written, and then I begin to grasp more fully the nature of the topic. Thus the onset of the nagging feeling that the topic I am discussing has already been fully developed by someone else, be that person a philosopher or a mathematician.

The process is rather frustrating, because I really begin to feel my own amateurism. Not that this embarrasses me — I simply don’t believe in writing about things multiple times. I don’t wish to waste the reader’s time. There is a body of truth out there, and this body is not something that need be made more murky than necessary.

Point being, I need to let loose a bit with this stuff. It is infinitely frustrating, though.

Yeah, I haven’t been working on this much lately. Things have been hectic, and I haven’t exactly been loving the format.

I think I will continue to work on the answers and posting them to github, and maybe making an occasional blog posting, highlighting what I’ve gotten from the book, or some sort of good solution that I rather enjoyed doing. But so far, the book has been fantastic.

Hopefully I’ll have a new one done soon.

For exercise 1.46

;; sicp exercise 1.46
;; iterative-improve will be copied to lib/iterative-improve.scm

(load "../lib/average.scm")

(define (iterative-improve good-enough? improve-func)
  (lambda (guess) (if (good-enough? guess)
                      guess
                      ((iterative-improve good-enough? improve-func) (improve-func guess)))))

(define (sqrt x)
  (define (make-improve x)
    (lambda (guess) (average guess (/ x guess))))
  (define (make-good-enough? x)
    (lambda (guess) (< (abs (- (square guess) x)) .001)))
  ((iterative-improve (make-good-enough? x) (make-improve x)) 1.0))

(define (fixed-point f first-guess)
  (define tolerance 0.000000000000001)
  (define (close-enough? guess)
    (< (abs (- guess (f guess))) tolerance))
  ((iterative-improve close-enough? f) first-guess))

(fixed-point (lambda (y) (+ (sin y) (cos y)))
             1.0)
;; answer should be something around 1.2587315962971173
(sqrt 16)