Re: William T. Parry gets rid of Disjunction introduction

On 2026-07-04 07:21, olcott wrote:
> On 7/4/2026 1:47 AM, Mikko wrote:
>> On 03/07/2026 18:04, olcott wrote:

>>> P ⇒ Q
>>> P → Q
>>> P ⊃ Q
>>>
>>> are all abolished and replaced with the binary
>>> form of logical necessity: P □ Q

There is no 'binary form of logical necessity. □ is a unary operator and 
an expression like P □ Q makes absolutely no sense.

If you want to use this as a binary operator you'd actually need to 
*define* it. You don't seem to grasp this. You can't just introduce a 
new operator and expect people to know what it means.

Also, moving into the domain of modal logic would be an incredibly 
strange thing for you to do given that in previous posts you claimed to 
reject the idea of models. But modal logic is *replete* with models. 
Modal logic operates over a set of many models. □P means that P is true 
in all accessible models of the system.

André

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