Skip to Content.
Sympa Menu

coq-club - Re: [Coq-Club] Why do we have "Prop < Set" ? Why not just "Prop ≤ Set" ?

coq-club AT inria.fr

Subject: The Coq mailing list

List archive

Re: [Coq-Club] Why do we have "Prop < Set" ? Why not just "Prop ≤ Set" ?


Chronological Thread 
  • From: Guillaume Melquiond <guillaume.melquiond AT inria.fr>
  • To: coq-club AT inria.fr
  • Subject: Re: [Coq-Club] Why do we have "Prop < Set" ? Why not just "Prop ≤ Set" ?
  • Date: Thu, 19 Jan 2017 13:55:02 +0100

On 19/01/2017 13:48, Matej Kosik wrote:

>> As I explained, that is because A:Prop implies A:Set holds, but the
>> converse does not.
>
> Not even when:
> - Prop and Set have no inhabitants
> - or Prop and Set have the same inhabitants
> ?

If your question is about some other formal system with different
definitions of Prop and Set, then yes, all bets are off. Otherwise no,
bool:Set does not imply bool:Prop in Coq.

Best regards,

Guillaume



Archive powered by MHonArc 2.6.18.

Top of Page