A couple good books I’ve read lately:

Incognito: The Secret Lives of the Brain, by David Eagleman.  The first third of the book is the best; it’s a demolition of the idea that we run our brains.  That is, there’s this thing we call us, the conscious mind, and like a bad manager, it takes credit for its underlings’ hard work.   This is not a novelty in philosophy, but Eagleman is a neuroscientist, so his examples of how the conscious mind isn’t in control are based in neurology and psychology, and they’re fascinating.

One of his examples: you know how to change lanes, correct?  Can you explain it, as a short sequence of instructions for a smart (and English-speaking) robot?  Give it a try.

Most people say something like “Turn the wheel right; when you’ve moved over, straighten it out.”  If the robot tried that, it would steer off the road.  The thing is, after turning the wheel right, you have to turn the wheel an equal amount left in order to get back to your original direction.  Your brain knows this, but you probably don’t.  Any skilled behavior like this has been shuffled off to unconscious routines which manage all the details (and far more fluidly than the conscious mind could do them).

After this he reviews some theories of mind; he like Minsky’s Society of Mind, but extends it to include a multitude of competing sub-units– what he calls a “team of rivals”.  Another of his metaphors is an electoral system.  This broadly makes sense, though I think Eagleman overestimates how revolutionary it is: it’s an updated version of the theory of mind put forth in medieval allegories.

Then he gets into issues of responsibility, including legal responsibility.  We used to blame the person for everything; now we think that some things, like mental illness, are ‘not the person’s fault’.  He suggests that we go all the way and just admit that nothing is anyone’s fault. This doesn’t mean that we don’t punish anyone; it means that we take a scientific view of what it takes to prevent bad behavior from recurring.  This last part of the book is the least convincing, as by now he’s gone far beyond our actual knowledge.

The Secrets of Alchemy, by Lawrence M. Principe.   This is a history of alchemy, from its origins in Hellenistic Egypt, through the Arab period, and then to medieval and Renaissance Europe.  I read a lot about alchemy while researching substances— the history of alchemy is basically the history of chemistry.  And it’s fun stuff, especially for the beautiful names– orpiment, realgar, the Green Lion, calx of lead, spirit of hartshorn…

Alchemy has a bad rap because, of course, the alchemists were mostly pursuing an impossibility: the transmutation of metals by chemical methods.  Principe answers the obvious question– why didn’t they notice it was impossible?– by analyzing their methods, their principles, and their idea of authority.  Briefly:

  • with (by modern standards) inconstant heating methods and no good tests for purity, it was hard to replicate results and thus easy to think that someone else had done better
  • the best physical theories, going back to the ancients, said that metals were compounds
  • people claimed to have succeeded, and the whole medieval mindset was to trust written sources attributed to known experts.

So the alchemists thought they had good evidence, and their critics (and there were many) had the same limitations, and couldn’t actually disprove the claims.  (There was a lot of fraud, to the point that alchemists in literature are almost always comic figures.)

The most interesting bits are where Principe digs out the retorts and Bunsen burners and attempts to follow old recipes.  His conclusion is that the old alchemists were often careful observers– though they were wont to disguise their knowledge as what sounded like insane mystical ramblings:

Take the ravenous grey wolf that on account of his name is subjected to bellicose Mars, but by birth is a child of old Saturn, and that lives in the valleys and mountains of the world and is possessed of great hunger.  Throw the king’s body before him that he may have his nourishment from it. And when he was devoured the king, then make a great fire and throw the wolf into it so that he burns up entirely; thus will the king be redeemed.

That’s some instructions by Basil Valentine, from 1602.  Principe explains that this is a real experiment: the king is gold; the wolf is melted stibnite, or antimony ore.  A 14-karat gold ring is 58% gold, 42% copper.  Throw it in melted stibnite and it dissolves. The copper turns into a sulfide, while the gold and antimony meld together and sink to the bottom, where they can be easily retrieved.  Roast this mixture and the antimony evaporates, leaving you with pure gold.  So this is an obfuscated but correct recipe for purifying gold.

Why did the alchemists write this way?  Well, they didn’t always; there are examples of very straightforward books.   But it’s clear that the writers were masters of PR.  You didn’t want to give all your secrets away; and if your early steps could be puzzled out, it added authority to the more fanciful steps describing the creation of the Philosopher’s Stone.  Principe describes and reproduces a few quite striking experiments– not transmutation, of course, but chemical tricks that could wow a rich patron.

In the 1900s, a lot of this mystical-sounding obfuscation was reinterpreted as actual mysticism– that is, it was taken as a spiritual rather than a chemical process.  This was a wrong turn; much better to think of alchemy as early chemistry, with a commendable interest in hands-on experimentation.

Principe obviously loves this stuff, and probably makes a few too many excuses for the alchemists.  It’s true that it’s not edifying to simply make fun of early thinkers for bad theories or poor methods.  One Arab alchemist, for instance, had the excellent idea of quantifying the notion of how much of the four humors were active in a substance– there were 28 degrees of hot, cold, wet, and dry.  So far so good, but how did he assign the degrees– some kind of crude measurement?  No, he took the Arabic name of the substance, letter by letter, and applied numerological rules to derive the degree.  Principe carefully explains that this is not as silly as it sounds– it was in accordance with the best Islamic thought, in which Arabic was God’s language, and could be expected to match aspects of God’s creation.  Well, that is an interesting glimpse into an earlier worldview, and you might want to incorporate things like that into your conworld.  But, well, that line of thought was ultimately sterile, and alchemy was not really medieval thought at its best.