In an essential way I make use of Frege’s and Vasilev’s ideas. N. A. Vasilev distinguished two levels in a logic. The abstract logic depends on gnoeologic assumptions while the empirical part of logic depends on ontological ones. Vasilev did not change the external logic but he did change the internal one. His system can be viewed as a non-standard syllogistics based on classical propositional logic . Vasilev’s ideas become plain if we discern cleary acts of predication and acts of (...) assertion, the relation of mental contents with the way things are. The second sourse of the idea seems to Frege’s differentation of mental process and assertion, statement . As a symbol of assertion for Frege serves a vertical stroke |. A horizontal stroke following it is correlated with holding a proposition, it makes the sign determined everywhere. In the string of signs the one following the vertical stroke does not express a proposition, it describes a possible state of affairs. (shrink)