I have tried and errored a reasonable amount of times

[Chris Angelico]

On Thu, Sep 4, 2014 at 9:17 PM, Denis McMahon <denismfmcmahon at gmail.com> wrote:
> On Wed, 03 Sep 2014 07:16:34 +0000, Steven D'Aprano wrote:
>
>> Who uses + for disjunction (∨ OR) and concatenation for conjunction (∧
>> AND)? That's crazy notation.
>
> The way I was taught it in the mid 1980s, a.b === a and b, a+b === a or b.

The middle dot is another notation for multiplication, as is abuttal
(not actually concatenation, in this context). So they're all saying
the same thing: boolean 'and' is multiplication, boolean 'or' is
addition.

ChrisA