Can we ever have $\Gamma \models \perp$? I think since as long as $\Gamma$ has a model, $\Gamma \models \perp$ can never be correct. So it is correct when $\Gamma$ has no model. Is my understanding right?
Thanks in advance!
Can we ever have $\Gamma \models \perp$? I think since as long as $\Gamma$ has a model, $\Gamma \models \perp$ can never be correct. So it is correct when $\Gamma$ has no model. Is my understanding right?
Thanks in advance!
That's exactly right: "$\Gamma\models\perp$" is equivalent to "$\Gamma$ has no model" (or "$\Gamma$ is unsatisfiable").