While you could say programs are pure syntax, they are executed on real machines and have real effects. If those capabilities don't count as semantic content, I don't know what does.
That is correct, you don't know what semantic content is.
Care to explain?
Meaning.
The words on this page mean things. They are intended to refer to other things.
Oh. and how do you know that?
Meaning is assigned, it is not intrinsic to symbolic logic.
Assigned by us, I suppose? Then what makes us so special?
Anyway, that's not the most important:
None of this means we might not someday build an artificial brain that gives rise to an artificial conscious mind. But it won't be done on a von Neuman machine.
Of course not: von Neuman machines have limitations that would make them too slow. But even in principle? I have a few questions for you:
Recent article in The New Yorker:
http://www.newyorker.com/online/blogs/newsdesk/2012/11/ibm-brain-simulation-compass.html
Here is the research report from IBM, with the simple title "10^14":
http://www.modha.org/blog/SC12/RJ10502.pdf
It's nothing like a real brain simulation, of course, but illustrates that hardware to do this is getting very close.
There is likely to be quite a long overhang between the hardware and the software...