What is the important distinction between cohesion and coherence

What is the important distinction between cohesion and coherence?
【正确答案】：Cohesion refers to the linguistic devices of the text, and is thus a textual phenomenon: we can point to features of the text which serve a cohesive function. Coherence, on the other hand, is in the mind of the writer and reader; it is a mental phenomenon and cannot be identified or quantified in the same way as cohesion. In other words, coherence refers to establishing logical and functional connections between the ideas and concepts presented, and has a lot to do with mental processes of understanding. Cohesive devices, on the other hand, highlight the surface-structure connections between elements of discourse. Coherence takes precedence; if ideas are not coherent, there is no text.