Concession describes a relationship of "unexpectedness" between two or more propositions ("ideas") in the discourse. In some way, one of the ideas is a "surprising" or "illogical" continuation with reference to the other(s). For example :
He's terribly unpunctual, rarely does any work, and is really inefficient. However, they've decided to promote him.
Although it was pouring with rain, we decided to go for a long walk.
Markers of the concession relationship may be :
Prepositions - despite, in spite of
Conjunctions - but, although, though, even though
Adverbials - However, Nevertheless, Nonetheless, All the same, Regardless
Concession should not be confused with contrast - where the propositions are "opposite" in some way, but where there is no suggestion of resulting "illogicality" or "unexpectedness". The two facts are separate :
My house has two bedrooms whereas John's has three.
I can't read Anne's handwriting, but Joanne's is clearer.
Markers of contrast may be :
Conjunctions - but, while, whereas
Adverbials - However, In contrast, On the other hand, Yet
Distinguishing between them
Notice that some markers can indicate both concession and contrast, while others are limited to only one of the relationships. This is another good way to decide the difference between them For example, whereas can only indicate contrast. It is impossible to say *Whereas it was pouring with rain, we decided to go for a long walk.
This tells you that the relationship between the two ideas must be concession rather than contrast.
Halliday, M.A.K and Hasan, R. 1976, Cohesion in English, Longman
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