Leonard Bloomfield

Leonard Bloomfield is nowadays principal representative of the Descriptivist school. 

Leonard Bloomfield himself studied linguistics in the traditional style, spending a year in his twenties at Leipzing and Gottingen working with some of the great figures of the neogrammarian movement, and his teaching responsibilities at various Mid-Western universities were concerned with Germanic philology

Franz Boas

Franz Boas, began his academic career as a student of physics and geopraphy, and it was thought the latter subject that he came to anthropology. The key to Boas's thought lay in the realization, borne in to him on his first field trip, that, contrary to what he had supposed, anthropology is not a branch of geopraphy - that is to say, the culture of a community is not simply a function of its material circumstances, and the human sciences are quite distinct both in contect and in methods from physical sciences.

The descriptivists

During the years at the end of the nineteenth and beginning of the twentieth centuries when Saussure was working out his ideas in Europe, synchronic linguistics was emerging independently, and in a very different style.

"Descriptivist linguistics" is the term used for the school founded by Franz Boas.

'A rich and adaptable instrument'

Halliday

The London School

London School

Functions of Language

The ADDRESER sends a MESSAGE to the ADDRESSEE. To be operative the message requires a CONTEXT referred to seizable by the addressee, and either verbal or capable of being verbalized; a CODE fully, or at least partially, common to the addresser and addressee; and finally, a CONTACT, a physical channel and psychological connexion between the addresser and the addresse, enabling bothe of them to enter and stay in communication.

Functional Linguistics: the Prague School

Morphology

Linguistic research on morphology and on the organization of the lexicon has not initiated any great changes in practical research over the last 20 years.
Applied-linguistics research on lexicography, terminology development, second-language acquisition, and language teaching is still employing descriptive approaches that have been in use for some time.

Saussure:language as social fact

Saussure: language as social fact Activity

Applied Linguistics & Linguistics

Applied Linguistics Activity

The Study of Language

Plato distinguish noun and verbs. Greek, Latin, Celtic and Germanic all had striking structural similarities.

Sir William Jones' discovery fired the imagination of scholars.

In the 20th century, the emphasis shifted from language change to language description. Ferdinand de Saussure is "the father of modern linguistic".  Saussure  suggesyede that language was like a game of chess, a system in wich each item is defined by its relationship to all the others. 'Structural linguistic' is sometimes misunderstood, all linguistics since de Saussure is structural, the language is a patterned system composed of interdependent elements.

Bloomfield considered that linguistics should deal objetively and systematic observable data (Bloomfield era). Items were identified and classified solely on the basis of their distribution which the corpus.

Discovery procedures: set of principales which would enable a linguistic to 'discover' in a foolproof way the linguistics units of a unwitten language.

Chomsky is the most influencial  linguist od the century. He claimed tha a grammar should be more humans description of old  utterence. It should  also take into account posibble future utterence.