begin with a thought experiment imagine that it 's four thousand years into the future civilization as we know it has ceased to exist no books
no electronic devices
no facebook or twitter all knowledge of the english language and the english alphabet has been lost now imagine archeologists digging through the rubble of one of our cities
with strange symbols on them
perhaps some circular pieces of metal maybe some cylindrical containers with some symbols on them and perhaps one archeologist becomes an instantcelebrity when she discovers buried in the hills somewhere in north america
massive versions of these same symbols
now let 's ask ourselves what could such artifacts say about us
to people four thousand years into the future this is no hypothetical question in fact
the indus valleycivilization which existed four thousand years ago the indus civilization was roughly contemporaneous with the much better known egyptian and the mesopotamian civilizations but it was actually much larger than either of these two civilizations it occupied the area of approximately one million square kilometers
covering what is now pakistan northwestern india and parts of afghanistan and iran given that it was such a vast civilization you might expect to find really powerful rulers kings and huge monuments glorifying these powerful kings in fact
what archeologists have found is none of that they 've found small objects such as these
a king a god
a priest or perhaps an ordinary person like you or me we don 't know
but the indus people also left behind artifacts with writing on them well no not pieces of plastic but stone seals copper tablets pottery
and surprisingly one large sign board which was found buried near the gate of a city now we don 't know if it says hollywood or even bollywood for that matter
in fact we don 't even know what any of these objects say
and that 's because the indus script is undeciphered we don 't know what any of these symbols mean the symbols are most commonly found on seals so you see up there one such object it 's the square object with the unicorn like animal on it now that 's a magnificent piece of art so how big do you think that is
perhaps that big
we need to decipher the script to answer that question deciphering the script is not just an intellectualpuzzle it 's actually become a question that 's become deeply intertwined with the politics and the cultural history of south asia in fact the script has become a battleground of sorts between three different groups of people first
you 'll see that most of the languages spoken in north india belong to the indo european language family so some people believe that the indus script represents an ancient indo european language such as sanskrit
and they say that perhaps sometime in the past dravidian languages were spoken all over india and that this suggests that the indus civilization is perhaps also dravidian which of these hypotheses can be true
we don 't know but perhaps if you deciphered the script you would be able to answer this question but deciphering the script is a very challenging task first there 's no rosetta stone i don 't mean the software i mean an ancient artifact
that contains in the same text both a known text and an unknown text
and why was i fascinated well it 's the last major undeciphered script in the ancient world my career path led me to become a computational neuroscientist so in my day job i create computer models of the brain to try to understand how the brain makes predictions how the brain makes decisions how the brain learns and so on
but in two thousand and seven my path crossed again with the indus script that 's when i was in india
and i had the wonderful opportunity to meet with some indian scientists who were using computer models to try to analyze the script and so it was then that i realized there was an opportunity for me to collaborate with these scientists and so i jumped at that opportunity and i 'd like to describe some of the results that we have found or better yet
let 's all collectively decipher are you ready the first thing that you need to do when you have an undeciphered script is try to figure out the direction of writing here are two texts that contain some symbols on them can you tell me if the direction of writing is right to left or left to right
i 'll give you a couple of seconds
okay right to left
and some other signs but never by these other signs at the bottom and furthermore there 's some signs that really prefer the end of texts such as this jar shaped sign
and this sign in fact happens to be the most frequently occurring sign in the script
and the computerlearned a statistical model of which symbols tend to occur together and which symbols tend to follow each other given the computer model we can test the model by essentially quizzing it so we could deliberately erase some symbols and we can ask it to predict the missing symbols here are some examples
and we can use the computer model now to try to complete this text and make a best guess prediction here 's an example of a symbol that was predicted
such a randomjumble of letters is said to have a very high entropy this is a physics and information theory term but just imagine it 's a really randomjumble of letters
has an intermediate level of entropy it 's neither too rigid nor is it too random
well linguistic scripts can actually encode multiple languages so for example here 's the same sentence written in english and the same sentence written in dutch using the same letters of the alphabet if you don 't know dutch and you only know english and i give you some words in dutch
you 'll tell me that these words contain some very unusual patterns some things are not right
two of them are shown here that have very unusual patterns so for example the first text there 's a doubling of this jar shaped sign this sign is the most frequently occurring sign in the indus script and it 's only in this text that it occurs as a doubling pair
it 's just like our english and dutch example and that would explain why we have these strange patterns that are very different from the kinds of patterns you see in the text that are found within the indus valley this suggests that the same script the indus script could be used to write different languages
the results we have so far seem to point to the conclusion that the indus script probably does represent language if it does represent language then how do we read the symbols that 's our next big challenge so you 'll notice that many of the symbols look like pictures of humans of insects of fishes of birds
use the rebus principle which is using pictures to represent words so as an example here 's a word
can you write it using pictures i 'll give you a couple seconds
except that this is the mother of all crossword puzzles because the stakes are so high if you solve it
and i want to mention that these seals were used for stamping clay tags that were attached to bundles of goods so it 's quite likely that these tags at least some of them contain names of merchants
and it turns out that in india there 's a long tradition of names being based on horoscopes and star constellations present at the time of birth in dravidian languages the word for fish is meen which happens to sound just like the word for star
and so seven stars would stand for elu meen which is the dravidian word for the big dipper star constellationsimilarly there 's another sequence of six stars and that translates to aru meen which is the old dravidian name for the star constellation pleiades
and finally there 's other combinations such as this fish sign with something that looks like a roof on top of it and that could be translated into mey meen which is the old dravidian name for the planetsaturn so that was pretty exciting
these seals contain dravidian names based on planets and star constellations well not yet so
we have no way of validating these particular readings but if more and more of these readings start making sense and if longer and longer sequences appear to be correct then we know that we are on the right track
ted in egyptian hieroglyphics and in cuneiform script because both of these were deciphered in the nineteenth century the decipherment of these two scripts enabled these civilizations to speak to us again directly the mayans started speaking to us in the twentieth century but the indus civilization remains silent
these are our ancestors yours and mine they were silenced by an unfortunate accident of history
生词表: