The Liars Paradox OR Today Is Not Opposite Day

Today my son Blake started telling me that “Today is Opposite Day!” and then said things like “I love doing my homework. Just kidding. It’s opposite day!”

I told him that he couldn’t possibly be telling me that today is opposite day. If it were opposite day and he was telling me it was opposite day, then it wouldn’t be opposite day. And if it’s not opposite day and he told me that it was opposite day, it would be opposite day. It’s a cycle that never ends. Formally the sentence, “This is opposite day” is neither true nor false and therefore is undefined.

The Infinite Circle of Opposite Day

This, of course, prompted his friend Gabe to try to explain it all to me. “It’s complicated,” he said, “you see, if we say it’s opposite day then we would say that it’s not opposite day to mean that it really is opposite day.” But I didn’t find this line of argument compelling.

Blake tried a different tack, “We can say that Wednesday is opposite day.”

“Yes,” I said, “but you can’t say that on Wednesday.”

This is an ancient logical paradox called the Liar’s Paradox which often takes the form of “I am a liar” or “This sentence is false.” Because the sentence is self-referential and negative.

I figure it’s never to early to teach the kids about logic and paradox. It also makes Blake be more specific about opposite day. The inherent problem with opposite day is that kids randomly choose which items are opposite and which are not (e.g., the sentence “It’s opposite day” is not negated). Now he needs to say “If it were opposite day, I’d say that I love doing my homework.”

Alexa and Google in Our Home

In our home, we have a rule that there are no phones at the dinner table. We do this so everyone is paying attention to each other — not their phones. When a person has a phone at the table, it lets them be alone, even if they are sitting in a group. It gives that person a superpower to transport their mind to a completely different place. People are alone together (per Sherry Turkle):

Teenagers Alone Together

When you have an Amazon Echo or Google Home, that is another entity in the room. Some people are worried about how kids are being rude to Alexa and how they will bring this rudeness to their interactions with people. I think this is a red herring. It’s much easier for kids to deal with a free standing AI like Alexa than trying to teach children how to deal with a human being combined with a smartphone.

When the iPad came out, many of the reviews highlighted how useful it was for children. It’s the same way with voice assistants. The kids will do a lot of exploring. You’ll want to lock the machines down these down to prevent purchasing everything on Amazon. We’ve learned a lot from our kids’ explorations, most interestedly that there are songs called I Pooped and Diaper Baby.

For reference, our setup is two Google Home Mini’s that are each next to a Chromecast. We also have an Amazon Echo in the dining room table.

Some other things that we use the voice assistant for:

  • To check the weather
  • To play music
  • For the kids to watch their TV show on Netflix
  • To turn on and off the TV (Chromecast + Google Home)
  • As an intercom (between the Google Homes)

Update (2/10/2018): There’s a great video about politeness and Alexa called Southern Alexa.

On Martin Luther King Day

Martin Luther King Day is more than just another day off from work. His widow Coretta Scott King goes through the meaning of the day and what it means. She says that:

Every King Holiday has been a national “teach-in” on the values of nonviolence, including unconditional love, tolerance, forgiveness and reconciliation, which are so desperately-needed to unify America…. Martin Luther King, Jr. Day is not only for celebration and remembrance, education and tribute, but above all a day of service.

So on this Martin Luther King day, my family and I participated in the Time of Good Day of Service. We visited an elderly homebound woman as part of the Dorot program. Dorot is a great organization that partners professionals and volunteers to enhance the lives of the elderly. They do a number of programs but the ones that are most relevant to us are the visits to the elderly around holidays. This is a great way for the kids to learn about charity — and there are relatively few charitable events that kids can participate in.

In this year where people are becoming more divided, it’s great to go and meet a stranger, learn from them and take part in our shared humanity.

BTW, this is an incredible video of two a capella groups, one Jewish and one African American, singing Shed a Little Light in honor of MLK day.

 

Winter Exercise — Stair War and Stair Chemistry Fluxx

We live in a 30 story building. In the summer the kids can run and play outside but in the winter they need to get their exercise inside the building.

So we started to climb the stairs inside our building. The building is 30 floors high so getting to the top is a nice workout. When Blake was about 3, he would climb to the top of the building with excitement. We even started learning numbers. We learned that there is no number 13 in our building — or is there? But as the boys got older they want to do something more exciting so we created a game called “stair war.”

The rules for stair war are the same as the card game of war but every time there’s a war you go up that number of flights of stairs. This makes climbing the stairs a bit more interesting. The game has a number of interesting properties:

  1. Each time there’s a war you go up on average 7 flights assuming you go up ten flights for J, Q, K, A
  2. One out of every 13 plays, on overage, is a war. There are 169 ways that cards can lay between hands 13 x 13. But only 13 of them are wars.
  3. On average that’s about half a flight on average for each card flipped you go up 7 flights every 13 plays.
  4. But there’s a lot of uncertainty which adds to the excitement. You don’t know when the war is going to happen!

Blake is 8 now so we can play more interesting games. Our new favorite is now Chemistry Fluxx (sample game) on the stairs. We play a game of Chemistry Fluxx and then go up 10 flights of stairs — repeat until exhausted. Chemistry Fluxx is part of the Fluxx series, a card game where the rules and goals of the game are always in “Fluxx.” Watch the sample game and you’ll get a good idea of how it works. We speed up the game by changing the initial rules to something to draw 2 / play 2 to speed things up. Also, Chemistry Fluxx teaches them a few chemistry facts while you play!

The Hidden Thirteenth Floor

In my apartment building, like many others, there’s no 13th floor. The floors go right from 12 to 14.

Some people in our building thought it would be funny to tell the boys that they lived on 13. The boys would look between 12 and 14 and say “But there is no 13.” Then they discovered something very interesting. The designers of the elevator pattern needed to make a “B” for the basement. In order to make the circles in the middle of the “B” they decided to make the design into a 13.

This isn’t an accident and is done with other logos and graphic designs. Take the FedEx logo for example.

I bet you never noticed the arrow.

Or the Amazon arrow that tells you that they sell everything from “A” to “Z.”

And there’s many more.

Now the boys ask everyone where the 13 is on the elevator panel. Boy are the adults surprised.

Decorating Your Home With Magnets

I’ve always been very envious of artists that decorate their spaces. I remember visiting Industrial Light and Magic and seeing all the different statues that were on top of peoples desks. In The Last Lecture, Randy Pausch shows how he painted his childhood bedroom — even including painting an elevator on the wall. It used to make me sad that I would never be able to decorate the walls like that and really make it my own. But then I discovered a solution … magnets!

Originally I thought it would be really cool to use magnetic paint on the wall. But then I learned that magnetic paint is good for putting flexible magnetic images on the wall, but not for hanging anything up. So I thought, “How can I make my house into a magnetic bulletin board?” Then I realized how much of my house is made of metal.

The radiator is made of metal…

… as is the front door is made of metal which is a collection of pictures and maps …

Note at the top of the door is some remnants of our sign from the women’s march including Blake’s wonderful artwork of Donald Trump in the middle of the “O.”

Our window frames are made of metal…

… as are the many of the joints where the joints in the wall where the drywall comes together…

… so we can post awards right at wall corners…

… and school assignments.

On the fridge we built some really cool things using  Magnaformers. We also use them to build some cool Platonic solids, Archimedean solids and Johnson solids (not pictured).

We use little superstrong neodymium magnets with clips to make sure that things stick.

 

Kid Stuff From 2017

(From my year-end email)

For the Kids

Dr. Seuss Books Read by Celebrities

Audible has a large number of Dr. Seuss Books read by Celebrities. Here’s a sampling.

Green Eggs and Ham and Other Servings of Dr. Seuss which includes my favorite — One Fish Two Fish read by David Hyde Pierce

  • “Green Eggs and Ham” read by Jason Alexander
  • “One Fish, Two Fish, Red Fish, Blue Fish” read by David Hyde Pierce
  • “Oh the Thinks You Can Think!” read by Michael McKean
  • “I’m Not Going to Get Up Today” read by Jason Alexander
  • “Oh Say Can You Say?” read by Michael McKean
  • “Fox in Socks” read by David Hyde Pierce
  • “I Can Read With My Eyes Shut” read by Michael McKean
  • “Hop on Pop” read by David Hyde Pierce
  • “Dr. Seuss’s ABC” read by Jason Alexander

The Cat in the Hat and Other Dr. Seuss Favorites

  • The Cat in the Hat read by Kelsey Grammer
  • Horton Hears a Who read by Dustin Hoffman
  • How the Grinch Stole Christmas read by Walter Matthau
  • Did I Ever Tell You How Lucky You Are? read by John Cleese
  • The Lorax read by Ted Danson
  • Yertle the Turtle, Gertrude McFuzz, and The Big Brag read by John Lithgow
  • Thidwick, the Big-Hearted Moose read by Mercedes McCambridge
  • Horton Hatches the Egg read by Billy Crystal
  • The Cat in the Hat Comes Back read by Kelsey Grammer

Nontransitive Dice

Nontransitive Dice are pretty amazing things. Basically, in these dice, when they are set up pairwise, one die will beat another 2/3 of the time. However, there’s no “best” die. Even though A beats B and B beats C, A DOES NOT BEAT C. I bought a wonderful pair of Efron’s Dice from the Museum of Math.  For the math nerd, you really have to get a set. They’re amazingly interesting and they really teach kids about probability in a wonderful way!

Without going into all the details, normally, when you play dice you assume transitivity:

  • If B beats A
  • And if C beats B
  • Then C beats A

Which sounds obvious; however, it’s not. take, for example, the game rock, paper, scissors.

Rock-Paper-Scissors from Wikipedia

In this case:

  • Rock beats scissors
  • Scissors beats paper
  • But rock DOES NOT BEAT paper.

How to Painlessly Get Your Kids To Memorize Facts