paragraph: what is it?

Many patterns have an only explanation. Look for instance at

N-t108

P-m06

But most give several explanations because the pattern responds to several or even to many concepts. Or, in other words, many concepts fit the pattern.

Look for instance at ptr N-t057

Pattern N-t057 supplies five explanations: A, B, C, D and E.

Now, every one of these explanations is a paragraph.

Paragraphs are called by capital letters arranged according to the Latin alphabet: A. B. C. D. E. F. G....