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I have some questions on Unit Resolution and Set of Support. Any help will be much appreciated. Thanks!

For unit resolution is it not complete only when we have no unit clause (clause with one literal) or is it also not complete when we cannot make any more resolvents using at least one unit clause?

For set of support strategy I know each resolution has to take a clause from the set of support, but can we get resolution from two clauses in the set of support, or do we have to do one clause from the auxiliary set and the other from the support set?

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    What do you mean with "unit resolution" ? The rule : from $A \lor B$ and $\lnot B$, infer $A$ ? or some "resolution procedure" ? – 2017-02-23
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    Maybe useful : [propositional logic resolution strategies](http://math.stackexchange.com/questions/1627473/propositional-logic-resolution-strategies) : "We initialize the auxiliary set to be the set $S$ (our starting set of clauses). We initialize the set of support to be the negated conclusion $\lnot G$. Our resolution will always use at least 1 clause from the set of support. All clauses derived by such action will be added to the set of support." – 2017-02-23
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    @MauroALLEGRANZA Unit resolution is what you said, but one clause may have arbitrarily many literals. (The other has one literal; hence the name.) It's the basic inference rule used in propositional SAT solvers based on the CDCL (conflict-driven, clause-learning) algorithm. – 2017-02-23
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    Unit resolution is not complete. Period. Oftentimes, we get some resolvents, but we then get stuck. – 2017-02-23
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    Alright, that makes sense. Thanks to both of you for your help. – 2017-02-23

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