  The structure of almost topological space is a variation of the concept of
topological space. It emerged as a formalization of a quantifier first order
not definable from the usual existential and universal operators, named the
quantifier of the plausible. Later, it sought a formalization in propositional
logical context, given a deductive and axiomatic system with algebraic model.
We will present these formal conceptions and as an original contribution, we
describe the propositional version of the logic of almost topological spaces in
tableaux.
