There are two basic models for a paragraph in academic writing:
Specific > General
Inductive paragraphs are structured by beginning with a specific example (possibly a quotation) and analysing it to reach a general conclusion. This may mimic your own train of thought as you developed the idea in your mind. Beginning a paragraph with a quotation to analyse roots your paragraph in the text and encourages close, analytical reading. On the other hand, it may not be immediately clear to your reader exactly what the point is, or how it relates to the other points you make.
General > Specific
Deductive paragraphs start with a general conclusion, and then demonstrate this conclusion with specific examples. This is probably the opposite to the way the idea developed in your mind, but it presents clearly to the reader what the point is in the very first sentence, and once the point has been established, it can then be argued with specific evidence. The reader can follow your argument and structure more clearly, as it is signposted at the beginning. On the other hand, it may lead to sweeping generalisations.
Neither of these is the 'correct' way to paragraph in academic writing in English (the deductive paragraph is perhaps more common in academic writing generally). It is partly a matter of personal taste, and the kind of point you want to make. You can certainly mix both styles in your writing to good effect. Whichever style you use, a paragraph is like a miniature essay, with an introductory sentence, a main body and a concluding sentence which gives rise to the next paragraph.
Read the following two paragraphs (they are from essays on different topics) and decide which of the two paragraph models they each follow. How effectively do they make their point and develop it?
Paragraph from: Was there an identifiable mid-century poetic represented by Thomas Gray and Edward Young, and if so, what were its distinctive features?
Despite at first appearing simply to regret that Knowledge "did ne'er unroll" her ample page, and that "Chill Penury" did its freezing work on the poor, Gray soon qualifies his position - the circumstances of the poor do not "circumscribe... alone/ their growing virtues, but their crimes confine"14 too. Gray questions the usually-accepted value of knowledge, power and opportunity, as they enable vice as much as virtue. He seems to realise the subjectivity of the human position by his disinterested moral analysis of social opportunity. His stanza:
Full many a gem of purest ray serene,
The dark, unfathomed cave of ocean bear:
Full many a flower is born to blush unseen,
And waste its sweetness on the desert air15
at first glance seems to obviously lament the "waste" of the flowers and gems, but it is only an attitude which judges all things by their worth to humans which would draw such a conclusion. Gems do no worse in unfathomed caves, and flowers probably do better without humans around to pick them - the qualities of these objects are not diminished by their unuse, just as the "uncouth rhymes and shapeless sculpture" of the graveyard monuments are not diminished by their unrefinement. The recognition of the eventual fruitlessness of human action and involvement, that "the paths of glory lead but to the grave"16 seems, if anything, to be defining characteristic of these graveyard poets. Young's Night Thoughts, too, in its contemplation of the wider fate of man from a seemingly external perspective, from which the speaker feels qualified to lay down maxims such as "all men think all men mortal, but themselves"17, acknowledges the subjective and flawed position of mankind - "heir of glory!... frail child of dust!"18.
Paragraph from: "Peasant" Poets: The relationship between authenticity and artifice
However, the structuring principle of her work suggests that the authenticity of Collier's representation of labouring life is sometimes sacrificed to both a poetic schema and her self-presentation as an authentic "peasant" poet. As her poem is a direct response to Duck's, she mocks and reworks many of his images and phrases. For example, Collier's
Our Toil and labour's daily so extreme
That we have hardly ever Time to dream.10
Responds directly to Duck's
Nor when asleep are we secure from Pain;
We then perform our labours o'er again11
This suggests that the material and language of Collier's poem is selected for a specific structural purpose and that the specific instances and processes described are communicated not for their typicality or authenticity, but rather as a means of sharpening her attack on Duck. Thus, her representation of labour is distorted by her poetic structure and her desire to prove herself an authentic voice is, paradoxically, a primary agent in undermining her pretensions to authenticity.
The first example uses an inductive model of paragraphing, examining a quotation in detail, with only a slight indication of where it will take its analysis and how it links to the previous point, and ending with a more general conclusion. This last sentence, if adapted, could equally have been used to open the paragraph.
The second paragraph follows the deductive model. It makes a clear general statement about the subject of the paragraph, and analyses the following examples in this light. It then ends with a more detailed conclusion which leads into the next paragraph.