Conversion to Uppercase
When symbols are read by Common Lisp they are converted to upper case.
Note carefully that this remark applies to the characters in symbols.
The characters in strings are not converted upper case.
To type a symbol containing lower case characters you can enclose the
symbol in vertical bars, as in |AbC| or you can put a ``backslash''
before each lower case character you wish to preserve, as in A\bC.
|AbC| and A\bC are two different ways of writing the same
symbol (just like 2/4 and 1/2 are two different ways of writing the
same rational). The symbol has three characters in its name, the
middle one of which is a lower case b.
