Why we don’t understand as much as we think we do: Jonathan Drori on

Posted by: Tedstaff

Starting with four basic questions (that you may be surprised to find you can’t answer), Jonathan Drori looks at the gaps in our knowledge — and specifically, what we don’t about science that we might think we do. (Recorded at TEDU, February 2007 in Monterey, California. Duration: 12:34.)


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Comments (6)

  • Tucker Bradford commented on Oct 2 2009

    This was fascinating. As a homeschool “teacher” I struggle to find the balance between active teaching and experiential learning. This talk provides a compelling argument for closer inspection of that balance.

    Beth, I guessed air because I figured that trees, like most living things are made largely of carbon. Since trees photosynthesize CO2 I figured that would be the most ready source of carbon.

  • wazer alwazer commented on Dec 18 2008

    Jonathan Drori
    An outstanding personality and a wonderful and amazing his questions and failed to answer when I heard
    Thank you, Jonathan Drori
    Thank you ted
    وزير | منتدى | تفسير الاحلام | منتديات | برامج | مكتبة | صوتيات | العاب | قصص | مقالات | اخبار | ملتقى | فيديو |

  • beth wood commented on Oct 19 2008

    please can someone explain to me a little bit more about trees obtaining their mass from air, I am so impressed and bewildered. Where does water from the earth fit into this scenario?

    • Roger Sun commented on Oct 3 2009

      Air has mass. To demonstrate, air is 78% nitrogen. You may not think nitrogen has much weight until you try and carry around a tank of liquid nitrogen. Much as we can pressurize it into another phase, so too can trees lock that tank’s worth up in their tissue.

    • Tim Lundström commented on Oct 3 2009

      Most of a tree’s mass is the mass of carbon compounds. The carbon comes from carbon dioxide extracted from the air.

    • Brett Side commented on Oct 7 2009

      yes, to oversimplify the process, plants take in CO2 and let out 02 and thereby net a molecule of Carbon in the transaction.

      The thing is that he’s absolutely wrong about planets in this solar system having a circular orbit. The earth’s orbit is in fact an ellipse, with the sun as one of the two foci. It’s only very slightly an ellipse though, and appears quite circular to the unassisted eye. He’s correct about distance not causing seasons though.

      think of the back slash and forward slash representing the angle of the earth and the equals sign being the suns rays , in the northern hemisphere we have the following:
      (SUN) ======== in Summer and (SUN) ======== / in Winter