Why I Love the Khan Academy

I recently mentioned that I love the Khan Academy, but I didn’t explain why.

Salman Khan, the principal behind the Khan Academy material, understands something very important that emanates throughout all of his lectures whether they be on calculus, projectile motion, or thermodynamics: There is a difference between knowing the name of something and knowing something. When Sal explains a concept he focuses on why it is what it is, not just what it is. When explaining a mathematical formula he tells you why it is so, and how you can derive the same with some fundamental knowledge, a little intuition, and deductive reasoning.

An example: When Sal explains how to find the change in distance over time in projectile motion physics he doesn’t focus on which previously prescribed formula is appropriate, but how you can always figure out what to do using the cardinal rule, d = v * t, and some common sense. Khan wants you to learn how everything fits together, not whether there’s a minus or square root in one or another exotic equation that he bestows upon you.

Salman reminds me of the father Richard Feynman described in his book, What Do You Care What Other People Think?:

The next Monday, when the fathers were all back at work, we kids were playing in a field. One kid says to me, “See that bird? What kind of bird is that?” I said, “I haven’t the slightest idea what kind of a bird it is.” He says, “It’s a brown-throated thrush. Your father doesn’t teach you anything!” But it was the opposite. He had already taught me: “See that bird?” he says. “It’s a Spencer’s warbler.” (I knew he didn’t know the real name.) “Well, in Italian, it’s a Chutto Lapittida. In Portuguese, it’s a Bom da Peida. In Chinese, it’s a Chung-long-tah, and in Japanese, it’s a Katano Tekeda. You can know the name of that bird in all the languages of the world, but when you’re finished, you’ll know absolutely nothing whatever about the bird. You’ll only know about humans in different places, and what they call the bird. So let’s look at the bird and see what it’s doing—that’s what counts.” (I learned very early the difference between knowing the name of something and knowing something.)

You can know all of the mathematical formulae in the world, or all the abstract concepts, but if you don’t understand why they are as they are, and how they fit together, you’re not going to get very far. I’m sure every teacher tries to convey this, but Khan puts them to shame. By focusing on the relationships between all of the topics he discusses he invokes an ever-repeating sense of “just getting it” — and that’s what really matters, not memorizing a bunch of equations for your exams.

I’m glad that thousands of people, rather than just a single classroom, enjoy his teachings every minute.

Khan Academy: Teach Yourself

I love Khan Academy! It is one of the largest repositories of good, enthralling educational videos on the planet, and it’s made by just one guy, Salman Khan. How awesome is that? So awesome, in fact, that Bill Gates is using it with his own kids, and that Google recently gave Khan $2 million to continue expanding his archive.

Here’s an introduction:

We’ve reached a point where anyone with internet access and some motivation can get a top-notch education using resources like Khan Academy and MIT OpenCourseWare. I think this is no less than the beginning of a revolution in the otherwise stagnate realm of education, and that it’s going to change the world!

Update: Here’s why I love the Khan Academy.

Interviews with 'Restoring Honor' Participants

I hope your Tuesday is going well so far. Should you feel the need to ruin it, though, just watch this series of interviews with participants of Glenn Beck’s “Restoring Honor” rally held on the 47th anniversary of Martin Luther King’s historic speech, “I have a Dream”:

“The best argument against democracy is a five-minute conversation with the average voter.” – Winston Churchill


Sometimes I catch myself merely living because I don’t have anything better to do. I wake up from a long slumber and realize that a year of my life just went by. I think about what I did in that year. Then my mind wanders. I think about life.

When some of Earth’s organic molecules first came together to form nucleic acids some four billion years ago, a sequence of events that would affect me rather significantly was set in motion. I’m talking, of course, about natural selection.

The first microbes evolved into cells, the cells into amoebas, the amoebas into multi-cellular organisms, they into plants and plant-like beings on the sea floor, these beings into fish, fish into amphibians, into reptiles, into rodents and other warm-blooded creatures, into ape-like ones, and, eventually, just a couple million years ago, they had evolved into humans. All we animals spread across the Earth, adding, in an inconceivable enormity of small but decisive events, to the tree of life that had set its first roots four thousand million years before.

Somewhere along that line, on a normal November day, I won the biggest game of dice. I swam fast on that day, just like my mother and father had before, and as the collective of their parents had, and as their parents’ parents, and as their parents, continuing down the line of crucial events all the way down to when the first human opened its eyes, and through every line in the history of each of all the species that came before us; through every minuscule genetic mutation; through everything that led to the creation of Earth itself: The expansion of the universe, the formation of galaxies, the creation and violent death of a billion billion stars, the chance creation of the Milky Way galaxy and, in that, our Solar System, and, finally, within that, the Earth. A very long process had simultaneously ended and begun anew. I was coming to life.

It is the most humbling and, at the same time, the most inspiring thing I can think of. Of all the humans who could ever have been, you are. You are here. You are alive. You had the greatest streak of luck. Instead of a thousand trillion other forms of life that could have been, you are. You are floating through a vast and magnificent universe on a small, blue marble with comparatively few, equally fortunate others.

You enjoy an instant of consciousness. Don’t waste it away.


Here’s Carl Sagan reading the chapter ‘Wanderers’ from his book, Pale Blue Dot, making the case for human venture into space, nicely edited together with video footage from various documentaries by Callum Sutherland: