294 a ferment that continued into the twentieth century

Ibid.

295 First used by Teilhard de Chardin

Ibid.

296 "Shortly after, the human era will be ended"

Vernor Vinge, "The Coming Technological Singularity: How to Survive in the Post-Human Era," 1993, http://www-rohan.sdsu.edu/faculty/vinge/misc/singularity.html.

297 form that can be comprehended by and contained in advanced computers

Lara Farrar, "Scientists: Humans and Machines Will Merge in Future," CNN, July 15, 2008, http://articles.cnn.com/2008-07-15/tech/bio.tech_1_emergent-technologies-bostrom-human-life/2?_s=PM:TECH.

298 "post-Singularity, between human and machine or between physical and virtual reality"

Ibid.

299 has challenged Kurzweil to a $20,000 bet

"By 2029 No Computer-or 'Machine Intelligence'-Will Have Pa.s.sed the Turing Test," A Long Bet, http://longbets.org/1/.

300 before the computer-based "Technological Singularity" is ever achieved

John Chelen, "Could the Organic Singularity Occur Prior to Kurzweil's Technological Singularity?," Science Progress, June 20, 2012.

301 replace not only hips

Ben c.o.xworth, "New Discovery Could Lead to Better Artificial Hips," Gizmag, November 27, 2011, http://www.gizmag.com/artificial-hip-joint-lubrication-layer/20949/.

302 knees

James Dao, "High-Tech Knee Holds Promise for Veterans," New York Times, August 18, 2010.

303 legs

Alexis Okeowo, "A Once-Unthinkable Choice for Amputees," New York Times, May 14, 2012.

304 arms

Thomas H. Maugh II, "Two Paralyzed People Successfully Use Robot Arm," Los Angeles Times, May 16, 2012.

305 but also eyes

Carl Zimmer, " 'I See,' Said the Blind Man with an Artificial Retina," Discovery News, September 15, 2011.

306 replaceable with artificial subst.i.tutes

Richard Yonck, "The Path to Future Intelligence," Psychology Today, May 13, 2011; Rob Beschizza, "Mechanical Fingers Give Strength, Speed to Amputees," Wired, July 2, 2007.

307 Cochlear implants, as noted, are used to restore hearing

"Cochlear Implants Restore Hearing in Rare Disorder," Science Daily, April 20, 2012.

308 exoskeletons to enable paraplegics to walk

Melissa Healy, "Body Suit May Soon Enable the Paralyzed to Walk," Los Angeles Times, October 6, 2011.

309 confer additional strength on soldiers

Susan Karlin, "Raytheon Sarcos's Exoskeleton Nears Production," IEEE Spectrum, August 2011.

310 bespoke in-ear hearing aids are already made with 3D printers