"C is not like a hammer, C is like wood. [...] Knowing all about the subtle details of working with wood isn't especially portable to working with cables that carry electricity or layers of carbon fibre or blocks of solid aluminum."
All metaphors leak, but this one seems leakier than its predecessor. Turing equivalence (http://en.wikipedia.org/wiki/Turing_completeness) tells us that any program can be written in any computer language. (Except SQL. But let's not get into Turing-incomplete languages now.) Whereas electric cables can't be made from wood.
The "hammer" metaphor, on the other hand, would suggest that you can do all kinds of woodwork with just a hammer; it's just needlessly difficult. Which seems more accurate.
All metaphors leak, but this one seems leakier than its predecessor. Turing equivalence (http://en.wikipedia.org/wiki/Turing_completeness) tells us that any program can be written in any computer language. (Except SQL. But let's not get into Turing-incomplete languages now.) Whereas electric cables can't be made from wood.
The "hammer" metaphor, on the other hand, would suggest that you can do all kinds of woodwork with just a hammer; it's just needlessly difficult. Which seems more accurate.