Don Geddis
My personal home page


HCSD School Board
PresidentVice PresidentMemberChairVice ChairCommissioner

HCSD School Board
Dec 2013-
Dec 2026
Governing Board Member, School Board
Hillsborough City School District
Commissioner, Hillsborough Recreation
HCSD parent volunteer
2012-2013West Trustee Representative
West Parent Group exec board
GATE committee
Judge, West ILab Tech Challenge
2011-2012West Trustee Representative
West Parent Group exec board
Judge, West ILab Tech Challenge
2010-2011Chair, West School Site Council
West Parent Group exec board
Webmaster, HCSD: Parents & SSCs
Judge, West ILab Tech Challenge
2009-2010West School Site Council
VP of R & D
VP of Technology, Shopping
Founder Cadabra
Tesserae Info Sys
1987-1995 Ph.D. (and Master's) in
Artificial Intelligence,
Computer Science
Stanford University
1984-1987 B.S., Computer ScienceStanford University

Martial Arts

In 1987 I started practicing Aiki Jujitsu in the self-defense club at Stanford University. In 1996 I was promoted to third-degree black belt.

In 1994, after watching Royce Gracie win the second Ultimate Fighting Championship, I started training in the Gracie style of Brazilian Jiu-Jitsu, the bulk of it at Ralph Gracie's academy in Mountain View. I competed in a few Brazilian jiu-jitsu tournaments in the past. I now train at Ralph's San Francisco academy. On May 6, 2008 Ralph promoted me to black belt. On June 30, 2018, Ralph Gracie promoted me to third-degree black belt in Brazilian Jiu-Jitsu.

Favorite Short Stories
  • The Lottery, by Shirley Jackson
  • The Veldt, by Ray Bradbury
  • I Have No Mouth, and I Must Scream, by Harlan Ellison

Favorite Novels
  • A Fire Upon the Deep by Vernor Vinge
  • The Polity novels (Cormac, Transformation, Jain) by Neal Asher
  • Pandora's Star by Peter F. Hamilton
  • Ancillary Justice by Ann Leckie


Inspired by LongBets.Org, and Julian Simon's 1980 bet with Paul Ehrlich on the future price of five metals.

Related efforts include and The Good Judgment Project.

I find it useful -- when people have a strong disagreement in their predictions about future world events -- to quantify the confidence of their assertions by associating it with hard cash. If nothing else, it causes all parties to take stock of what they actually believed at the time, and then avoid various kinds of experimental bias by actually following through to see what the outcome turns out to be.


Open Bets

UFOs (6/19/2023). Within 5 years (expires 6/19/2028) and 12 years (expires 6/19/2035), there will be public scientific consensus for at least one specific concrete artifact, technology, or humanoid visitor of non-human origin. Don Geddis says NO; Win Ark says YES. Stakes: 5 years 20:1 odds $500:$20; 12 years even odds $500.

Fusion power (3/26/2018). Within 20 years (by 2038), a power generation plant will be constructed that generates at least 100MW of net energy via nuclear fusion. Don Geddis says NO; Win Ark says YES. Stakes: Steakhouse or Brazilian Churrascaria dinner.

Go (12/23/2003). Lifetime, biannual, man-vs-machine bet on the game of Go.

Completed Bets

Full details are available for the summary below.

DateEventOpponent StakesOutcome
6/19/2023 UFOs (in 5 or 12 years) Win Ark$500:$20; $500 TBD
9/23/2020 Crocker DL: <15 in a grade for T2 Louann CarlomagnoDessert or coffee Win
5/9/2019 Game of Thrones Louann CarlomagnoRoot beer floats Draw
3/19/2019 HCSD School Bonds >$75M in 2020 Louann CarlomagnoDonuts Loss
9/26/2018 Kavanaugh on the Supreme Court Roger Avedon$1 Loss
3/26/2018 Fusion power (100MW) in 20 years Win ArkSteak or Churrascaria dinner TBD
11/23/2017 Natural-born citizen Kim Crellin$1 Win
7/16/2017 Boxing: Floyd vs. Conor (#4) Win Ark$10 ($1) Win
7/14/2017 Boxing: Floyd vs. Conor (#3) Win Ark$100 ($50) Win
7/13/2017 Boxing: Floyd vs. Conor (#2) Win Ark$5 Win
6/17/2017 Boxing: Floyd vs. Conor (#1) Danny Gong$10 ($1) Win
10/20/2015 11/2015 election: <3000 ballots Anthony Ranii$5 Win
8/19/2015 HCSD gifted testing opt-in <50% Angela O'DonnellLobster @ Kincaid's Win
12/15/2014 Nov 2015 election Margi Power$5 ($10) (x2) Win
11/2014 Urbanathlon Anthony RaniiLunch Loss
5/18/2014 Running (Will vs. Dusty), 10years@2x/yr Dusty Leary$12.50ea/$5K ($12.50) Win (x1)
2014 Return student to HCSD Angela O'DonnellEarrings Loss
12/25/2012 Hillary Clinton testimony Jim Geddis$5 Win
11/25/2012 Go #3 (man vs. machine) Joe Mathes$50ea ($200) Win (x4)
5/15/2011 Submission grappling: Geddis vs. Harvey Will Harvey$1ea/$100 ($2) Win (x2)
5/28/2010 Go #2 (man vs. machine) Dusty Leary$50ea ($50) Loss (1-7)
5/8/2010 UFC 113: Lyoto Machida vs. Shogun (II) Win ArkTruffles Win
1/31/2009 UFC 94: BJ Penn vs. Georges St. Pierre Win Ark$1 Win
5/24/2008 UFC 84: Tito vs. Lyoto Win ArkEspresso Loss
5/5/2008 Medical Prayer Win Ark$500 ($10) Loss
4/24/2008 Obama wins election Bill Mahoney$100 Win
4/17/2008 Peak Oil (bet #2) Win Ark$49 Loss
4/15/2008 Peak Oil (bet #1) Win Ark$100 Loss
4/14/2007 Bodog: Fedor vs. Lindland "Dude" & Arash$70 Win
12/30/2006 UFC 66: Liddell vs. Ortiz Arash$50 Win
11/18/2006 UFC 65: Hughes vs. GSP Batata$50 Win
5/27/2006 UFC 60: Hughes vs. Royce Arash & Batata$100 Win
9/22/2005 Efficient markets Win ArkPhoto Win
12/23/2003 Go (man vs. machine) Scott Roy$10ea ($450) Win (33-3)
4/2002 Overture/Google patent Narinder Singh$25 Loss

Open Source

ANSI Common Lisp
Asciify Convert a string with European accented characters, into "equivalent" 7-bit ASCII (A-Z,a-z).
Grid Make a blank grid suitable for crossword or cross-sum puzzles, with typical symmetry and connectiveness.

My Current Web Sites

URLTopicNotes Don GeddisMy personal home page Saltwater reef aquariumPhotos & video from home aquarium Aiki JujitsuArchive of my last version Brazilian Jiu-JitsuArchive of my last version

My Previous Web Sites

URLTopicNotes Gracie and Brazilian Jiu-JitsuJan 15 1996 - Sept 5 2006 (10+ years) Aiki Jujitsu at StanfordFounding webmaster, mid 1990's Rickson Gracie Founding webmaster, mid 1990's Ralph Gracie Founding webmaster, mid 1990's
www.doubleudoubleudoubleudotcom.comNothing, really OK, this one was a joke For encrypted email, use my PGP Public Key. Last updated 06/21/24