Coherence is the relationship, connection or union of things together, or that interconnecting or holds together the parts of a whole.
It is also known as coherence the logical and appropriate relationship that is identified between the different parts that make up a totality.
On the other hand, the consistent attitude of a person in relation to a position previously assumed is also called coherence. In this sense, when it is said that someone is coherent, it is because it is verified that there is correspondence between their way of thinking and driving.
The word, as such, comes from the Latin cohaerentĭa.
Textual coherence is the characteristic that is associated with the texts in which it is identified, among the units that compose it (sentences, paragraphs, sections or parts), coherence relations that allow them to be recognized as unitary semantic entities. In this sense, for a text to have textual coherence, it is necessary that the various ideas that build it, both the main and the secondary ones, are logically and effectively linked so that the reader can identify the overall meaning of the text.
We say that a book has textual coherence, for example, when we find that among all the chapters or parts that compose it, they are assembled according to a central theme. This same characteristic must be able to be identified at lower structural levels, in the relationships established between the different sentences and paragraphs that make up each section or chapter of the book.
As a global coherence, the thematic unity of a text is known, that is, the one according to which a text whose meaning revolves around a central theme is composed. In this sense, global coherence allows us to appreciate a text as a meaningful totality. As such, global coherence works at a macro level, providing meaningful relationships to different parts of a text.
As local coherence is called that which refers to the semantic relationships that are established between individual sentences in a sequence. As such, local coherence grants thematic unity to the segments that make up a text. In this sense, unlike global coherence, local coherence operates at a micro level.
Coherence and cohesion
The consistency is expressed through the semantic relationships established between the parties that make up text, which provide it with meaning and give it a meaning that can be understood by the reader. In this sense, coherence is a procedure that we can observe at a macro-textual level.
For its part, cohesion is associated with the relationships established between the elements that make up the text, that is, the sentences and the links that they establish among themselves to ensure the correct transmission of the message. Hence, it is considered that cohesion operates at a microtextual level.