Early Live Suzanne Vega Audio (1985)

While cleaning out our basement this morning, I happened upon some old audio cassettes. Two jumped out at me: recordings of live radio performances by Suzanne Vega. I’ve been a fan for a long time and was fortunate to have seen Suzanne perform live on several occasions in the early days of her career in Greenwich Village. These radio performances were both broadcast in early 1985, right around the time Suzanne’s debut album was released.

The first recording is a concert broadcast by WBAI in New York.

The second is a recording of Suzanne’s appearance on the late, great Pete Fornatale‘s show on WNEW in New York. This one is a combination interview, tracks from her then newly released record and an in-studio performance of Small Blue Thing.

Apologies in advance for the poor audio quality — these tapes are nearly 30 years old!

Why I Quit Facebook

Are you like me? Do you find yourself checking your Facebook news feed regularly and with ever increasing frequency? When you see a good movie, or take a cool photo, or experience something unique, is your first thought “I need to write a status update about that”?


One of the reasons why Facebook is so popular is because it gives us a little dopamine hit every time we find something we like. It’s a bit like fishing — hours of idle time can be justified by those few exciting moments precipitated by a fish tugging on your line. There’s an even bigger hit waiting for active posters: for many people in the 21st Century, the Facebook “like” button has become a surrogate source of validation, commiseration, therapy and love.

Whenever you find yourself indulging in repetitive behavior there are two important questions you should ask:

  1. Am I enjoying this behavior?
  2. Is this behavior making me a better person?
As I think about my Facebook use, I realize that my enjoyment of the experience has declined over the years as it’s become increasingly automatic and addictive. There is without question some high quality material on Facebook, however, the low signal-to-noise ratio means I need to spend a lot of time looking for those gems. 

That brings me to my answer to the second question: if anything, Facebook has made me a less interesting person. Because instead of reading books or blogs or taking an online course, or getting out in the real world and actually talking to other people, I’m wasting a non-trivial amount of my time sifting through the minutia of everyday lives.

I’m  not going to get into the privacy issues or the abysmal user experience or a bunch of other technical reasons why I dislike Facebook. Based solely on my answers to those two questions, I think it’s time for me to move on to pursuits that I enjoy more and that make me a better person. I plan to read more, write more on this blog (which I’ve neglected since starting a new job in 2011), and spend more time with my wife and daughter.

To my Facebook friends: au revoir, mes amis! You can continue to follow my random thoughts and ideas right here at http://marc1.org. And to all my friends, virtual and real:  may you find what you’re looking for in 2013.

My Six Election Heroes of 2012 (with videos)

  1. Nate Silver, who demonstrated the power of statistics and taught us to base our predictions on more data and less talk.
     
  2. ” You can’t have a United States if you are telling some folks that they can’t get on the train.” – Bruce Springsteen
     
  3. Chris Christie, a Republican (yes, a Republican!) who showed everyone that it’s possible to put constituents ahead of politics.
     
  4. Chris Kluwe, who outspokenly and eloquently advocates for equal rights in a challenging place — the NFL.
     
  5. Joe Biden, who restarted his campaign’s momentum by taking Eddie Munster to the woodshed.
     
  6. Barack Obama – coolest president ever?
     

Not This Time

November 4th, 2008 was a bittersweet night for me. Throughout that year, I’d been very involved in helping the Obama campaign so I was ecstatic about the outcome of the presidential election. But I was profoundly saddened by the narrow victory of Proposition 8 in California. I felt a strange mix of exuberance in knowing that we could elect the most qualified person for our highest office, regardless of the color of his or her skin, while at the same time realizing that, despite all our progress, some Americans were still more equal than others.

In 2010, my daughter, Maya, wrote this essay for her fifth grade school writing contest. I was very proud of her but I also feared that her dream was not likely to be realized any time soon. But today, only two short years later, Washington became the seventh state in the US to legally guarantee full marriage equality for all its citizens.

It’s a moment to celebrate but also a time to be wary, because after tonight the real fight begins. The haters will come and spend money and time and do everything in their power to promote their agenda of discrimination and intolerance, just as they did four years ago in California. But you know what? It’s not going to work. Not this time. Maya and I are going to make sure of that. Will you join us?

It’s the End of the Book As We Know It (And I Feel Fine)

Imagine you’re about to open a candy store. You’ll want your shelves to be overflowing with enticing treats so you’ll need to invest in some inventory. But candy has a finite shelf life so if you end up stocking too much inventory, you can lose a lot of money on unsold candy. Any business that sells physical goods faces this dilemma: you want enough inventory to match your customers’ demand – any more and you pay the cost of excess inventory; any less and you lose sales opportunities.

A physical bookstore faces the same dilemma. Although they don’t spoil the way candy does, books also have a shelf life because authors, subjects and genres ebb and flow with the tides of fashion and culture. Now think about a digital bookstore. Because digital media is so easy to copy, the inventory cost to sell one copy of an ebook is essentially the same as the inventory cost to sell a billion copies. Any media that can be stored and copied digitally has a huge economic advantage over the corresponding analog incarnation.

That, in a nutshell, is why printed books and traditional bookstores are not long for this world. It’s already started happening. Earlier this year, Amazon.com announced that, for the first time ever, they had sold more electronic books than their paper counterparts. Borders, the venerable chain of book superstores, declared bankruptcy this year.

I will miss the look and the feel of paper books and the excitement of browsing shelves full of mystery and drama and surprise. But at the same time, I look forward to a world where books are easier to find and transport, cheaper to buy, more fun to read, and more environmentally responsible.

Tomorrow I’m going on a trip for work, where I’ll need access to numerous programming books and related references. Instead of carrying this on the plane:


I’ll be carrying this:

Doesn’t that make more sense?

Matthew & Me

 
Which albums would appear on the soundtrack of your life? One of my top choices would be a pop/rock masterpiece from the 90s, Matthew Sweet‘s Girlfriend, a brilliant collection of songs, from beginning to end.

One of my favorite concert memories was seeing Matthew perform live at a small club in Bruges, Belgium. Fast forward twenty years: Matthew has a new record called Modern Art coming out on September 27 and this morning my wife and I got to enjoy an intimate acoustic performance at a local radio station. Matthew and I have both aged a bit since I last saw him, but his music sounds as good as ever. In addition to promoting the new record, he’ll be playing Girlfriend live, track by track, at a few gigs this Fall in celebration of that record’s twentieth anniversary.

Here’s some video footage I recorded on my iPhone this morning (sorry for the shakes), featuring Matthew and his friend playing “I’ve Been Waiting”:



Thanks to The Mountain 103.7 in Seattle for arranging this event!

No Tie, No Problem

 
Twenty nine years ago, I started my first and, up till now, only job, at Bell Labs in Holmdel, NJ (the lobby of which is pictured above). Bell Labs was a magical place in those days, sort of like a cross between a corporate think tank and a Grateful Dead concert. There were really smart people everywhere, all sorts of clubs and activities and seminars and colloquia (I once got to see Steve Jobs, then CEO of NeXT, give a scintillating talk to a small audience, before he was bigger than God). The best part was that everyone dressed in jeans and t-shirts (and even shorts in the Summer). That was a big deal for me because I’ve always hated the idea of having to wear a tie to work every day. Bell Labs was a place where no one cared how you looked or how you dressed – you were judged only by your ideas and your attitude.

For someone interested in computer science, this a was fascinating time and place. In the basement, behind heavily fortified walls, were four huge, multi-million dollar IBM mainframes, all of which were kept busy around the clock by computationally demanding scientists and engineers. One of my first assignments was to write system programs for those mainframes in something called Basic Assembly Language, a low level programming language for IBM mainframes. Our developer tools were laughably primitive by today’s standards, but programming at that low level was a great learning experience. Plus I managed to crash one of those expensive mainframes all by myself. But it left me feeling convinced there had to be a better way to develop software.

During this era, some Bell Labs researchers (principally Dennis Ritchie and Ken Thompson) invented something so innovative and so revolutionary that it forever changed how people used computers. Unix and C were an epiphany for me: this was how operating systems and programming languages were meant to be. Forty years after it was invented, C is one of the two most widely used programming languages and Unix continues to influence generations of operating systems. Before long I got a chance to develop software in C on Unix systems and there was no going back for me.

Several years later, I was working at an R&D office in Columbus, OH, which was co-located with a giant factory and I noticed that every day around 4pm thousands of factory workers would line up like cattle by the exit gate, waiting for the clock to strike the top of the hour so they could punch out and leave work at the earliest possible moment. At the time, I was captivated by a software project. Though I was paid for a nominal forty hour work week, at the end of the day I couldn’t tear myself away from the office and I regularly worked nights and weekends, just because I wanted to. So when I saw all those workers who couldn’t wait to leave their job at the end of the day, I realized how lucky I was to have a job I loved so much that I didn’t want to go home.

Over the years, I’ve been fortunate to have worked with many smart and interesting and kind people and that experience has taught me a great lesson. If I were asked to give one piece of advice to a young person just starting out, it would be this: Always try to surround yourself with greatness, because great people will challenge you and inspire you to be like them.

Two days ago, the following window popped up on my laptop, reminding me it was my last working day at Bell Labs/Lucent/ALU:


At the moment, I was immersed in some code, still trying to write the best software I could, right down to my last hour (I actually worked overtime on my last official day :). Next month I start a new job with Google in Seattle. For me, it feels like coming home, returning to a place frequented by brilliant, unconventional and interesting people, a place where you can dress any way you like, and a place where people are judged not by how they look but by the quality of their ideas. I can’t wait. And, thankfully, I still won’t have to wear a tie.

Google+ = Facebook + Twitter + A Whole Lot More

Humans have two very strong impulses (among others): the need to be part of a group and the need to seek out new and interesting information. When we spend time with our families, join a club, or go to a party, we’re feeding that need to belong. When we read a book or browse the web, we’re feeding the need for new information.

Facebook facilitates sharing information within social groups. It’s a very powerful concept, one that appeals directly to the human need to socialize. In fact, I believe it strengthens group connections, which is why we see so many old friends and classmates reconnecting on Facebook.

What about the other need I mentioned – the need to find new information? That’s where Twitter comes in. Twitter is many things to many people but the primary value I see in Twitter is the ability to follow the thoughts and ideas of some of the world’s most interesting people. Whether you’re interested in news, sports, science, technology, or the latest comings and goings of Lady Gaga, Twitter has proven a remarkably timely and powerful source of information, usually beating the major news organizations to the punch.

Each service’s dominant usage model reinforces its unique value: Facebook users tend to focus on two-way “friendship” relationships, which facilitate group interactions, while Twitter users tend to accumulate one-way “follower” relationships, enabling them to monitor people they find interesting.

The newest arrival on the scene, Google+, implements a hybrid model: Google+ users can establish one-way follower relationships as well as bi-directional friend-like relationships. In this way, Google+ offers the best of both services. At the same time, it’s innovative design overcomes some critical shortcomings in both services (e.g., Five Things I Hate About Facebook).

So when my friends ask me what Google+ is all about, I like to says it’s basically everything you already like about Facebook and Twitter, plus better usability and a whole lot more cool stuff I haven’t even mentioned (like circles and group video conferencing). And for people like me, who’ve gotten used to reading and posting on two completely different services, all that goodness is now available in one place – that may be the biggest deal of all.

Saturday Puzzle #28 – Ones and Zeros

I like puzzles that are easy to state and don’t require a lengthy explanation. Today’s puzzle falls into that category. It comes from my good friend of 30 years, Ken O’Brien, who asked me this simple but perplexing question: “What is the smallest number evenly divisible by 225 that contains only the digits 1 and 0?”

If you’re not able to find the answer analytically, see if you can solve it algorithmically. In other words, see if you can come up with a procedure (brute force method or something more efficient) for finding the answer and leave me a comment with your results (I’ll post the answer on Tuesday). Oh, and by the way, don’t try to use ones and zeros for commercial purposes – they’re patented.

Solution: I know of three ways to solve this problem:

  1. The Slow Search Method – This approach starts with 225 and multiplies it by an ever-increasing sequence of integers looking for a number that contains only ones and zeros. Here’s the Python code to implement this method:

    import time
    
    start = 225    # starting number
    num = start
    cnt = 1
    binary_digits = ('0', '1')
    keep_looking = True
    
    # capture start time
    start_time = time.clock()
    
    while keep_looking:
        num += start
        # check for all 1s and 0s in num
        keep_looking = False # assume we found desired number
        for i in str(num):
            if i not in binary_digits:
                keep_looking = True # nope, not the desired number
                break
        cnt += 1
        
    elapsed = time.clock() - start_time # calculate elapsed time
    
    # we exit the above loop when we've found the desired number
    print('after', cnt, 'iterations and', elapsed, 'seconds:', num)

    Which prints the following result:
    after 49382716 iterations and 83.33 seconds: 11111111100

  2. The Fast Search Method – This strategy observes that the desired result looks like a binary number (albeit in base 10) so it tests a sequence of binary numbers, treating each as a base 10 number, looking for one that’s evenly divisible by 225. This is much faster than the previous method because it automatically skips all the base 10 numbers that have digits other than 1 and 0. Here’s the Python code:

    import time
    
    def convert(num, b1, b2):
        '''convert the passed num from base b1 to base b2'''
        result = 0
        digits = []
        while num:
            digits.append(num % b1)       
            num //= b1
        digits.reverse()
        for i in digits:
            result = (result * b2) + i
        return result
    
    start = 225
    num = 1000 # start with smallest possible answer > 225
    cnt = 1
    
    # capture start time
    start_time = time.clock()
    
    while True:
        if (num % start) == 0:       
            break
        # convert to base 2, increment, then convert back to base 10
        num = convert(num, 10, 2)
        num += 1
        num = convert(num, 2, 10)
        cnt += 1
        
    elapsed = time.clock() - start_time # calculate elapsed time
    
    # we exit the above loop when we've found the desired number
    print('after', cnt, 'iterations and', elapsed, 'seconds:', num)

    which prints the following result:
    after 2037 iterations and 0.04 seconds: 11111111100

  3. The Analytical Method – Because 225 ends in 25, multiples of 225 will end in one of four possible digit pairs: 25, 50, 75 or 00. The only one that meets our requirements (only 1s and 0s allowed) is the last one so we know that the result must end with two 0s. We can also see that 225 is divisible by 9 (recall the rule from grade school about summing the digits to check if a number is divisible by 9) and, therefore, any multiple of 225 must also be divisible by 9. Thus, the digits in the result must also sum to 9, so the smallest possible number meeting our requirements will contain nine consecutive 1s and will end with two 0s: 11111111100.

Obviously the fast search method is much more efficient than the slow search method (nearly 50,000,000 fewer loop iterations and 2,000 times faster) but the analytical approach is the clear winner because it doesn’t require any searching at all. The most efficient program of all is the one you don’t need to write. :)

Switched At Birth?

A lifelong friend of mine, who lives in Colorado, recently engaged the services of a local real estate agent and was so struck by the guy’s resemblance to me that he sent me a photo. I think the upper half of his face is a dead ringer (including the gray hair in the same spot). Here’s a side-by-side comparison of me and my doppelgänger:

Marc

Not Marc

 
 
 
 
      Weird, huh?

Five Things I Hate About Facebook and (Mostly) Like About Google+

I’ve always appreciated an old bumper sticker, which was particularly popular and relevant during the Bush (Jr.) years: “If you’re not outraged, you’re not paying attention”. When I think about Facebook, a variation on that theme comes to mind: “If you like Facebook’s user interface, you’re not paying attention”. In this article, I’ll explore five important design flaws in Facebook’s user experience and comment briefly on how Google+ deals with each.

Editing
You’ve entered a status update and sometime later realize it contains an error. You now have two choices, neither of which is very satisfying: delete and re-create the update (in which case you lose any accumulated comments/likes/etc.) or comment on your own update with an awkward, after-the-fact correction. Why can’t I simply click an edit button and fix my update?

The only counter-argument I can imagine is that someone could change an update after others have commented on or liked the original version, which could be abused in various ways. But we already face that pitfall in many places. For example, I can post an article on this blog, gather comments on the original version and then deceptively update my post later. Thankfully, blog software designers understood that preventing a small minority of people from abusing a feature doesn’t justify denying valuable functionality to all users. [Google+ got this right - status updates (and comments!) can be edited any time, even after they've been posted.]

Email
Facebook has its own independent messaging system, separate from any existing email system. This means that the email system I know and love, which has all kinds of great features (e.g. it does good things with conversation threads, it’s tightly integrated with my mobile device, etc.), along with years of my previous correspondence, is unusable within Facebook. This also means I end up with conversations being recorded in two different places. When I want to find an old message, I need to figure out whether it was part of a conversation that took place on gmail or Facebook. I may end up having to search both sites to find an item of interest.

In addition, Facebook’s messaging system lacks some basic functionality. The ability to forward a message was added only recently. Have you noticed that a message originally sent to a group can’t be replied to individually? Any replies go to all original recipients, whether you like it or not. And have you noticed there’s no notion of separate conversations or threads – every message is part of a never ending conversation with that particular recipient. [Email in Google+ appears to defer to your home email address/system. That's precisely how it should be - I already have an email service I'm happy with and I don't want my social networking services trying to duplicate or subsume that function.]

Navigation
Pop quiz: go to facebook.com and see if you can figure out how to block a friend (not unfriend them, just hide their updates from your news feed). Let’s see, “Friends”, then “Manage Friend list”, then…nope. OK, how about “Profile”, then “Friends”, nope. Let’s try “Account”, then “Edit Friends”, no, that’s not it. After googling “hide a friend on facebook”, I found the answer. Facebook is full of such navigational challenges. [Based on my usage so far, I'd say that Google+ offers much more intuitive navigation and organization.]

Privacy
Have you noticed how facebook keeps introducing new features that affect how your news feed looks, or worse, how much of your personal information is shared with others? Most of us find out about these changes through a friend’s status update that usually goes something like this: “Hey everyone, I just found out Facebook changed our default setting for X to Y. Here’s how to undo that change.” Much has been written about Facebook’s track record in this area. This graphic makes the point more clearly than any words I can add here. [I don't have enough experience yet with Google+ to assess their treatment of privacy and opt-in vs. opt-out policies.]

Search
Have you ever tried to find an old status update on Facebook? Here’s how it generally goes: click on username, scroll, scroll, scroll, click “older posts”, scroll, scroll, scroll, click “older posts” again, die of boredom. Is there any reason I can’t enter a search string to find my (or another user’s) old updates? [I don't see a way to search for old updates on Google+ either so this appears to be a shortcoming on both services. I'm interested to see which service adds this first. I'm starting my stopwatch now...Ready, set, go!]

Saturday Puzzle #27 – Let’s Make A Deal!

Today’s puzzle is so much fun and so counter-intuitive (accomplished mathematicians often get this one wrong), that I created a whole web site for it, hosted on Google App Engine.

You can find the website here: http://montyhallpuzzle.appspot.com. It includes a Javascript simulation, so if you don’t believe the answer you can try it for yourself. There’s also an “Auto-Run” capability which runs many trials very quickly. Enjoy!

Saturday Puzzle #26 – The Eight Queens Problem

You don’t have to be a chess player, or even know the rules of chess, to have a good time with today’s puzzle. All you need to know is that the queen is the most powerful chess piece – she can move as far as she likes in any direction: forward and back, sideways to the right or left, and diagonally. The diagram on the right illustrates the queen’s awesome power.

Today’s challenge is to place eight queens on a chess board such all 64 squares are attacked and no two queens are attacking each other. To make this puzzle easy and fun, I’ve created a custom software simulation, which you can use to try to solve it yourself right here on my blog (so you don’t even need a chess set). Just click on a square below to add a queen, and keep going until you’ve placed eight queens or run out of space with fewer than eight. You can click on an existing queen to undo a placement and there’s a reset button below the board in case you want to start over. You can also click the “solve” button to have your computer quickly find a random solution (there are many). Have fun and leave me a comment if you manage to solve this one!

Queens placed: 0 Covered (occupied + attacked) squares: 0

Saturday Puzzle #25 – Penny For Your Thoughts

IMG_7961 by Drown, on Flickr
Creative Commons Attribution-Share Alike 2.0 Generic License  by  Drown 

Imagine a very wealthy and eccentric friend (which is the best kind of friend to have) offers you the following choice:

  • One penny on the first day of January, two cents on the second day, four cents on the third day, and so on, doubling the amount you receive each day up to the 31st day of January.
  • One million dollars

Which option would you choose?

Solution: Today’s problem illustrates the power of a geometric series. It starts out very slowly, 1 cent, 2 cents, 4 cents…it seems like child’s play but by the end of the month, watch out! The number of pennies you receive on day N is given by 2 raised to the power N-1, which we can write mathematically like this: f(x) = 2**(x-1). The following graph of this function illustrates the sudden, rapid growth of a geometric series:

On the last day of January you would receive 2**(N-1) = 2**30 or 1,073,741,824 (over one billion) pennies, which is more than 10 million dollars! But it gets even better because we have to sum the pennies received throughout the entire month of January. The sum of all pennies received through day N is given by (2**N) – 1, which, in our case, would be (2**31)-1. That comes to 2,147,483,647 cents or, roughly, 21.5 million dollars.

Congrats to Simon Banks, Morag Livingston, Mudassir Ansari and Neal Starkman, all of whom wisely chose the pennies. Neal also pointed out the need for penny wrappers and hired help, which presumably can be paid with a portion of your $20M windfall.

Song of the Day #200 – The Milk Carton Kids

After ten months and 200 articles, this is my last Song of the Day for a while. I hope you’ve enjoyed this series — it’s been a labor of love. For my last entry, I’m featuring a song called Permanent, which I had the good fortune to see performed live a few nights ago. The Milk Carton Kids, comprised of LA-based singer/songwriters Joey Ryan and Kenneth Pattengale, form a powerfully synergistic package: talented singers with exquisite harmonies, complementary guitar styles (Ryan plays rhythm to Pattengale’s amazing improvisational skills), superbly original songs and laugh-out-loud stage patter. On top of all that, the lyrics to this song are beautiful (reproduced below). The last line is one of the best I’ve ever heard.

Permanent by Joey Ryan

Well I think I’m gonna work construction
Just to make something of myself
I can’t live off these childhood trophies on my shelf
Now I wanna get my hands dirty
I wanna feel a burning in my legs
I want more than the receipt for what I paid

Because everybody loves something new
Cause you can open it and plug it in
And it feels like a good night’s sleep
Like the girl you like paid you a compliment
They can keep the change and they can keep it coming
They can talk to who’s listening
But I’m still looking for something a little more permanent

I am not a poet
Show me the easy way and I’ll do it
No one could ever say that I’ve been trying way too hard
Cause everything that I have ever owned
Got dusty and old
So I threw it out just to make myself some room

I’m like everybody, I love something new
Cause you can open it and plug it in
And it feels like a good night’s sleep
Like the girl you like paid you a compliment
They can keep the change and they can keep it coming
They can talk to who’s listening
But I’m still looking for something that I can die with

If my luck is running out
Please don’t let it be so with love
It’s been a long year but I’m not ready to give up
Cause even if I lay ten million bricks
And they break through the summer haze
Someone’ll come around and bulldoze ‘em down some day

Because everybody loves something new
You get rid of what came before
And it feels like a long hot shower
Like getting in your bed when the sheets are warm
They can keep construction and they can keep coming
And I won’t be listening
Cause I found something a little more permanent
Oh yes I found someone that I can die with

Bonus video: here’s another great live performance; this song is called Queen Jane.

Saturday Puzzle #24 – This Puzzle Has Its Ups and Downs

One of the nice things about living in Seattle is that on clear days we get a great view of Mt. Rainier. Considered an active volcano, Mt. Rainier is the third-highest mountain in the lower 48 states at 14,411 feet, and the most ice-covered, with 25 major glaciers covering 34 square miles (source).

Let’s imagine that at noon one day you set out from the base of Mt. Rainier and you reach the summit exactly 24 hours later, at noon the following day. You pause for a few moments to take in the view and celebrate your accomplishment and then you turn around and head back down the mountain. You may or may not travel the same route down the mountain but assume the descent takes exactly the same amount of time as the ascent: 24 hours on the dot. Thus, you spend precisely two days on this venture, one day going up and one day coming back down (in reality, the climb and descent would take less than a full day but I’m taking a bit of “puzzle license” here).

Here’s the big question: during those two days spent going up and down the mountain, was there a point where you were situated at the exact same elevation, at the exact same time of day? (For example, at 10:42:29pm on both days you were exactly 6,531 feet above sea level). Leave me a comment with your guess below.

Solution: Congrats to Al Pessot, Katy Gustafson, Dylan Gustafson, Mehmet Said, Doug Needham and Muzaffer Peynirci, all of whom found that there is sure to be one time of day when you are at precisely the same altitude.

The rigorous but esoteric way to prove this fact is to use something called the intermediate value theorem from calculus. But there’s a much simpler and more intuitive way to understand this puzzle. Instead of thinking about one person climbing and then descending a mountain, imagine two people – one starting at the bottom and one starting at the top, ascending and descending in parallel. At some point, those two climbers are guaranteed to pass each other, altitude wise, at precisely the same time.

Al Pessot came up with a formulation which makes this point more dramatically: imagine the two climbers are constrained to follow the same path up and down the mountain. At some point, they will literally bump into each other, and that point will be, of course, at the same altitude and time of day.

Finally, Katy Gustafson came up with an interesting “border case” solution I hadn’t considered: the ascent and descent start and end, respectively, at the same altitude and time of day (base camp at noon), which is absolutely correct. Sometimes the easiest solution is the one right in front of your nose. :)

Saturday Puzzle #23 – Lighten Up

Light Switch by krossbow, on Flickr
Creative Commons Attribution 2.0 Generic License  by  krossbow 

You are standing in a hallway with three light switches. Each switch has an accurately labeled on and off position. In an adjoining room, behind a closed door, there is a bare lightbulb, which is controlled by one of the three switches. The other two switches are not connected to anything. You are free to manipulate the switches any way you like and for as long as you like, and you are permitted to enter the room containing the lightbulb once and only once. If and when you exit the room, you must close the door behind you – you are never permitted to view the lightbulb while manipulating the switches.

Here’s your challenge: figure out which of the three switches controls the lightbulb.

Solution: This blog may not have a lot of visitors but I sure do have some smart, creative readers. The comments below make one thing abundantly clear: there are multiple correct answers to this week’s puzzle. People found solutions involving roasting human hair, monitoring power meters, breaking the switches, installing a doggie door, self-electrocution, and several other ideas, which you can read about yourself below. My favorite solution, and the one I had in mind, goes as follows:

  1. Set switch #1 to the on position and switches #2 and #3 to the off position.
  2. Wait ten minutes.
  3. Turn switch #1 off and switch #2 on.
  4. Enter the room and examine the bulb. If the bulb is on, then it’s controlled by switch #2. If the bulb is off and warm or hot, then it’s controlled by switch #1 (because it was recently left on for ten minutes which caused it heat up). If the bulb is off and room temperature, then, by process of elimination, it must be controlled by switch #3.

Song of the Day #199 – Reggie Watts

Today’s song is by the multi-talented comedian, musician, beatboxer and singer, Reggie Watts. Reggie is so funny that he comes across as a comedian, first and foremost, but the longer you listen, the more you realize he’s making some serious music. Like another of my favorites, Flight of the Conchords, Reggie exists in the exquisitely enigmatic space between comedy and music. Plus, when’s the last time you’ve heard a hip-hop song performed in a golf sweater and featuring the word “pancreas”? Enjoy this clip of Reggie singing a song about Brown History Week live on Late Night with Conan O’Brien.

Random thoughts about technology, politics and the arts.