I have recently started reading Dennett’s From Bacteria to Bach and Back. The area of research covered in this book is mostly foreign territory, but I am currently on a visit to Tufts and did not want to miss the opportunity to learn from one of its best known thinkers. I even used the opportunity to contribute comments on the book to an online forum for Tufts students.
Here is a comment I had on chapter six:
In chapter six Dennett contrasts his notion of semantic information with the notion found in Shannon and Weaver. I want to get closer to the core of the notion of semantic information by looking at the various definitions and approximations offered in chapter six. Here is a list:
- “I will call them instances of semantic information, since we identify the information of interest to us on a particular occasion by specifying what it is about (events, conditions, objects, people, spies, products …)” (P. 107)
“semantic information, that is, information identified as being about something specific” (p. 112)
“So let’s consider, as a tentative proposal, defining semantic information as design worth getting” (p. 115)
“Semantic information, then, is “a distinction that makes a difference.” (based on MacKay, p. 116)
“My proposed definition of semantic information is close to his 1950 definition of “information in general as that which justifies representational activity” (MacKay 1968)” (p. 117)
These definitions and approximations are fairly diverse, but two elements stick out to me: aboutness and purposiveness. Aboutness is clearly identified in the first two definitions and it arguably figures in the notion of representational activity as well.
Purposiveness is included in the notion of design and in the notion of making a difference (see page 117 for this). Perhaps the interest in definition (1) is also pointing at the purposiveness associated with semantic information? Justification, as mentioned in MacKays definition (4) also seems to hang together with purposiveness. At least that is one plausible interpretation.
So we have two elements, aboutness and purposiveness. Are they equally important? Could there be a form of information that is even broader than semantic information? For example, information that is about something without any purposiveness to it?
Again, I am not overly familiar with this research and my questions might be misguided or the answers trivial within the debate. In any case I would like to get answers or explanations, why my questions are misguided.
p.s.: It has been suggested to me that the words “aboutness” and “purposiveness” were problematic. Is this the case? If so, is the problematic element introduced by my interpretation or Dennett’s text?