Abstract In this work, the diachronic perspective is used to explain the coexistence in current Spanish of three constructions: a) syntactic structures like a ver (si) + complement, integrated into the sentence framework, b) non-sentence fragments like a ver and c) independent structures, like a ver si + sentence complement. Out-side the sentence framework, both non-sentence fragments and independent sen-tences fulfil pragmatic values (interactive) or discursive values (favoring the construction of discourse). To carry out this diachronic investigation, we start from the syntactic insubordination hypothesis (cf. Evans 2007; Evans/Watanabe 2016), assuming that independence structures are the result of their insubordination from the governing nucleus of the sentence framework. In the first place, according to the documentation provided by the Corpus del Diccionario histórico de la lengua española (CDH), it is verified when the integrated syntactic structures like a ver (si) + complement, which we call experimentation structures, begin to be documented and when they stabilize in the language. The body of documents is subsequently reviewed to verify the first cases of syntactic insubordination and to verify how these syntactic independence processes end up being conventionalized and start to function as procedural marks with pragmatic and discursive value.