What does the term 'logical connectives' mean?

Explanation

Per the key, logical connectives state logical form together with its context — the explicit 'therefore', 'although' that the passage finds often unnecessary.

Note: Passage II (from William Empson, Seven Types of Ambiguity, 1930) is copyrighted and is not reproduced. Its argument: logical connectives are often unnecessary or misleading; the 'forces' that hold a poem's ideas together are mostly carried inside the ideas, so ideas are easier to name than forces; forces and ambiguity are complementary, so forces cannot be discussed simply as ambiguity; where a poem holds a contradiction, the tension must be conveyed and sustained.