[MD] Arlo's Rant and 3rd levels

[Arlo Bensinger]

[Ham]
Secondly, a human being in isolation is perfectly capable of 
inventing his own symbols, such as musical notation, sign language, 
mathematical equations, as well as coming up with a new language if necessary.

[Arlo]
That simply is wrong, and it denies every bit of evidence out there. 
Maybe you should read up on Helen Keller to see if a "human being in 
isolation" is capable of inventing a "language". There is also no 
evidence that the few feral humans we've studied that any of them had 
anything resembling a symbol system whatsoever.

[Ham]
How else could these conventions have been created in the first place?

[Arlo]
By human beings in social activity. Symbols are born only in the 
mutuality of human interaction, never "in isolation".