ronk wrote:gsf wrote:first, the proposition constraint P(FN) is not considered guessing in this context

(...)

about using backdoors, its a fallout from the definition of the P (proposition) constraint

each proposition can have 3 outcomes: contradiction, solution, inconclusive

In this context the primary purpose of the proposition is to find a contradiction. If a secondary purpose of the proposition is to solve the puzzle, then it is guessing IMO.

I remember discussions related to this a while back and didn't understand how

collateral information gathered by a technique must be dropped just because it leads to a solution

what solver, human or machine, ignores such gifts?

anyway, I defined P to have 3 outcomes and to use them

its most definately a mechanical / brute force technique

devised to characterize puzzles when combined with batched moves

it gives a reasonable estimate on the difficulties tree search and other

solvers would have arriving at a solution

and it maps back to terms familiar to me way back in grad school w.r.t.

ai / image processing / constraint satisfaction / backtrack search problems

just to be clear: I didn't define P to be the next greatest technique

its a means to characterize and parameterize the current batch of hard problems

in terms of the basic techiques in scope