According to Grice, the meaning or the intention is entailed by the expression. Whenever one says something or utters a statement x, it is not that the person only means x, s(he) also knows that y must mean that x. this particular analysis of knowing the intention by meaning it, Grice calls a non-naturalistic way of defining meaning. It is non-natural in the sense that meaning is not a causal process. The natural or causal notion of intention based semantics is associated with behaviouristic and physicalistic mode of meaning analysis.  The behaviouristic tendency always emphasizes a causal account of meaning, i.e., speaker’s intention produces or causes a typical effect in the listener’s mind, and thereby it maintains a conditional and causal approach to the analyzing communication intention.² As Avramides points out, “The causal theorists recognize that to account for meaning one must pay attention to the role of speakers and hearers. Their behaviouristic roots require that whatever it is speakers and hearers that are relevant to meaning should be accessible to observation.”³ The causal explanation of speaker’s intention with reference to the intentional aspect of mental life gives a naturalistic interpretation of the notion of IBS. On the other hand, the non-naturalistic account of IBS, according to Grice, must deal with the explication of  the notion like, “means the same as”, “understands”, “entails” and so on and the utterances which are specifically “informative or descriptive”. (op.cit., p.381)