A.I. Explanation:

First sentence: Why this is the first line? This paragraph is the first sentence because it introduces the main topic of free will. It gives a broad overview of the subject without going into details. This follows the rule of Topic Sentence. Why other lines are not chosen? The other paragraphs are not chosen because they do not stand alone. For example, Paragraph 2 starts with 'It', which is a pronoun and needs context. Paragraph 3 starts with 'Philosophers', which assumes prior knowledge. Paragraph 4 starts with 'Conversely', which shows a contrast and needs a previous idea.

Concluding sentence: Why this is the last line? This paragraph is the last sentence because it wraps up the discussion on free will and determinism. It presents the opposing view clearly, which gives closure to the topic. This follows the rule of Conclusive Words.

Paragraph pairs:

• Pair 1 (Paragraph 1 → Paragraph 2): Paragraph 2 connects to Paragraph 1 because it continues the idea of free will. The word 'It' refers back to 'Free will', showing a clear link. This follows the Noun Pronoun Rule.
• Pair 2 (Paragraph 2 → Paragraph 3): Paragraph 3 connects to Paragraph 2 because it gives an example of who debates free will. The mention of 'Philosophers' shows a logical order from the general idea of debate to specific thinkers. This follows the Broader to Specific Strategy.
• Pair 3 (Paragraph 3 → Paragraph 4): Paragraph 4 connects to Paragraph 3 because it presents a contrasting view. The word 'Conversely' shows that it is discussing a different perspective on free will. This follows the Contrast rule.