A.I. Explanation:

First sentence: Why this is the first line? This paragraph is the first sentence because it introduces the main idea. It does not refer to anything before it. It is a general statement about how people see the world. 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 'Even,' which is a conjunction. Paragraph 3 uses 'He' which is a pronoun that refers back to a person. Paragraph 4 starts with 'His,' which is also a pronoun. These reasons make them not independent.

Concluding sentence: Why this is the last line? This paragraph is the last sentence because it wraps up the main idea. It summarizes how customs affect beliefs. It brings together the earlier points about seeing the world and understanding truth. This follows the Summary Style rule.

Paragraph pairs:

• Pair 1 (Paragraph 1 → Paragraph 2): Paragraph 2 connects with Paragraph 1 because it continues the idea of how people see the world. The phrase 'He sees it' shows a logical flow from the first sentence. This follows the Logical Order rule.
• Pair 2 (Paragraph 2 → Paragraph 3): Paragraph 3 connects with Paragraph 2 because it adds more detail about the limitations of seeing the world. The word 'Even' shows a contrast to the previous idea. This follows the Contrast rule.
• Pair 3 (Paragraph 3 → Paragraph 4): Paragraph 4 connects with Paragraph 3 because it explains how stereotypes affect beliefs. The phrase 'His very concepts' shows a logical continuation of the thought. This follows the Logical Order rule.