[FOM] Mathematical explanation

[Neil Tennant]

On Mon, 24 Oct 2005, mjmurphy wrote:

> ... there is an example of Searle's (borrowed from Wittgenstein, but I 
> don't quite know where).  The example involves the mathematical proposition 
> 3 + 4.  

That's not a proposition, but let's not bother ...

> Imagine two overlapping circles, A and B.  A contains three dots, B 
> four.  However, two of the dots fall into the area where A and B overlap. 
> Here, Searle and LW contend, A + B = 5.  

The sum of two circles cannot be a number. If you mean, instead (on
behalf of Searle and LW), that the sum of the number of dots in circle A
and the number of dots in circle B is 5, then of course that's a howler.
The sum of the number of dots in circle A and the number of dots in circle
B is 7. 

If you could supply a reference for this howler in Wittgenstein's
writings, it would be most useful. It would reveal a remarkable, not to
say incomprehensible, degree of conceptual/mathematical illiteracy on the
part of one regarded as a philosophical genius, who held the genius Frege
in such high regard.

Neil Tennant