by Patrick Appel

A reader writes:

You posted an article today by Jonah Lehrer in which he posits “All the low-hanging facts have been found.” This reminds me a great deal of a famous quote by Charles Duell, then commissioner of the US Patent office, who in 1899 said “Everything that can be invented has been invented.” I think Lehrer over-simplifes what “low-hanging facts” are. I remember learning about relativity as early as elementary school. Who’s to say in the next 40 years someone won’t come up with The Grand Unifying Theory of Physics and that my grandchildren won’t be learning about THAT in elementary school, and 100 years down the road that won’t become the new “low-hanging fact”? All of this is relative. What we have known for decades seems obvious, and obfuscates the difficulty, magnitude, and importance of those discoveries.

Another reader argues along the same lines:

I don't know that any discoveries have been "easy." It's true that you used to be able to set sail, find a new land, claim it, and document new peoples and new species there, but there were trade laws, a limited flow of information (did Spain claim that same island two years ago?) and poor scientific instruments, complicated taxonomic protocol, and, the biggest hurdles of all, religious doctrine and entrenched interests. Let's not forget that the most significant discoveries and theories of the past few hundred years faced (and, in Darwin's case, continue to face) strong religious challenge and even persecution.

Current and future discoveries face even higher hurdles. As obstinate as church and state may be, lay people could understand when a scientist when he discovered a new species of bird, or a new function of the human body. But how many lay people in 2011 can understand the latest discoveries of quantum physics, biochemistry, or climatology? I would argue we still have not realized the cost of popular Luddite culture and politics. How difficult a task the scientist now faces, when discoveries still meet the old hurdles of status quo and stagnant faith, and the new hurdles of a skeptical and apathetic populace. They may have imprisoned Galileo, but how much worse to ignore him and confine his discoveries to obscure cable channels and trade publications? And how different the Roman Church's forced confession, and the ongoing climate denial taking place at the highest levels of US society?

A final reader:

How do you measure discovery?  If you measure it simply by finding a new human organ or finding another asteroid, then of course the  Law of Diminishing Returns set in long ago and discoveries will likely be less dramatic or less significant.  But if you measure it more broadly or more multi-dimensionally, there doesn’t appear to be any fall-off.  We’ve “discovered” the personal computer, distant galaxies and planets, and the human genome.  Twenty years ago, HIV was considered a death sentence, rubbing bone-on bone in your knee meant you were effectively crippled for the rest of your life, and premature babies under two pounds didn’t have a very optimistic prognosis.  Discoveries and inventions have dramatically changed the way we live.

Hold the area of discovery constant and ultimately the Law of Diminishing Returns will set in, perhaps rather quickly.  But so much of the discovery process is discovering things that we didn’t know that we didn’t know, opening new areas for discovery.  The argument that “all the low-hanging facts have been found” has been made since before the Enlightenment.  It wasn’t correct then, and I’m very doubtful that it’s correct today.

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