3. In the last quarter of the last century, Slobin went back to Relativists' Sapir-Whorf Hypotheses to develop his 'thinking for speaking' thesis. He considers that “experiences are filtered though language into verbalized events” (1996: 75), that is to say, that language is not a sharper but a filter. Therefore, all the devices that speakers use to encode within linguistic terms their experiences constitute 'thinking for speaking'. This idea entails that, if people learn particular ways for 'thinking for speaking' in their native language, to learn a foreign language does not implies to have a good deal of knowledge of its grammar rules and a rich vocabulary but, it also involves to learn an appropriate 'thinking for speaking' in that target language.
4. While dealing with transfer, we cannot avoid to comment the 'Multiple Effects Principle' which gave place to two interesting concepts developed by Andersen and Kellerman in the last two decades of the last century. Without any kind of doubt, transfer is an important phenomenon to take into account in SLA and Andersen regards it as a filter “that governs the learner's perception and retention of specific features of the second language (L2) input” (1983: 117). He considers that the natural processes that a student of a target language acquires, together with the perception of the target language's structural relations with the source language, serves as a “catalyst for transfer to operate” (1983: 178). This phenomenon gave place to what he called 'Transfer to Somewhere Principle', so to say: A grammatical form or structure will occur consistently and to a significant extent in interlanguage as a result of transfer if and only if (1) natural acquisitional principles are consistent with the L1 structure or (2) there already exists within the L2 input the potential for (mis-) generalization from the input to produce the same form or structure. (1983: 182)
![[object Object],Early works published during the first half of the last century already show a general agreement on the close connection between language and conceptual structures. Dan I. Slobin (1996: 70), in an article on thought and language, mentions the influence of authors like Von Humboldt, Whorf or Boas, who stated that language conditions the way we perceive and analyse the world and, what is more, language can even determine which aspects of our experiences must be expressed. Taking into account some linguistic theories that can be considered as the first step towards 'Conceptual Transfer', we can draw our attention for a while on the controversy that took place between 'Universals' and 'Relativists'. On the one hand, 'Relativists' consider that language shapes the speaker's thought and therefore, every language represents a different conceptual experience depending on its own features because, as Whorf said, language influences beliefs and behaviours. On the other hand, with the advance of cognitive sciences in the second half of the last century, 'Universals' considered that thought was crucial to shape the say in which speakers use language due to the importance given to socio-cultural aspects and to the attention drown to meaning and discourse. This rich intellectual climate propitiated the rise of a great number of studies that, little by little, brought together different theories that gave place to the idea of 'Conceptual Transfer'.](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)