Sentence:  All four lines of the pattern are required to establish that "hot" and "cold" are <WSD>antonyms</WSD>. / "The water is hot" entails "The water is not cold". / "The water is cold" entails "The water is not hot"./ "The water is not hot" does not entail "The water is cold". / "The water is not cold" does not entail "The water is hot". 
Meaning of the word marked with <WSD> tags:  A word that describes one end of a scale, while its opposite describes the other end, such as "large" versus "small"; a (gradable antonym).