In some logical settings (e.g., classical logic, in which a certain so-called deduction theorem holds), this is equivalent to the provability of a conditional, but in some settings, it is not.
The forms that the study of these logical constants take are described in greater detail in the article logic, in which the different kinds of logical notation are also explained.
For the first time logicians had a fully formal deductive logic powerful enough to represent all valid deductive arguments in mathematics and the sciences a logic in which the validity of deductive arguments depends only on the logical structure of the sentences involved.
"Au contraire," Charlotte answered with tortured logic, a logic in which no one but James believed.
The Birds unfolds with a dream logic in which the birds are a punishment for Daniels.
Phanias is mentioned as the author of works on logic, in which he probably followed Aristotle's doctrine.
But as we settle into the work, Khan's choreography creates its own urgent, atmospheric logic in which plot and character move naturally in and out of focus.
Evans shows that Nazism was all the more effective for its irrationality and arbitrariness: there was no logic in which to take refuge.
Mr. Murakami said that hearing this kind of hermetic logic, in which any act or situation can be explained away, brought him strangely back to his own fiction.
That army set off a decade-long conflagration, mostly devoid of ideology or even tribal logic, in which Sierra Leonean government troops as well as rebel soldiers raped and incinerated civilians on a massive scale.
The sequences aren't exactly stories, but they follow a kind of dream logic in which "we" and "I" do various things in the first sequence, with a "you" emerging more fully in the second.
