The object of this paper is to show why recent research in the psychology of deductive and probabilistic reasoning does not have.

Conversational implicatures do not normally fall within the scope of operators because they arise at the speech act level, not at the level of sub-locutionary constituents. Yet in some cases they do, or so it seems. My aim in this paper is to compare different approaches to the problem raised by what I call 'embedded implicatures': seeming implicatures that arise locally, at a sub-locutionary level, without resulting from an inference in the narrow sense.

In this paper I describe how the authors involved in the scalar implicatures debate develop only partially co-extensional theories of scalar implicatures starting from a common range of core facts. I consider three components of the scalar implicature mechanism: the exhaustivity operator, the alternatives generation and the avoid-contradiction procedures.