The Japanese title, like the English title, constitutes a complete sentence. "Wagahai" = "I" (a lordly, archaic version of this pronoun), "wa" is the topic marker, meaning that the foregoing "I" is the topic of this sentence, "Neko" simply means "Cat," and "de aru" is a very formal, scholarly way of saying "am" (or, depending on the context, "is").

Because of the cognitive dissonance generated by the contrast between the speaker (a wretched and totally worthless stray cat) and the solemn formality and the supreme arrogance of the statement "Wagahai wa neko de aru" (the arrogance lies in the use of the pronoun "wagahai") the title constitutes a totally untranslatable joke.

In closing, let us note that the author's surname is "Natsume." The "o" in "Soseki" is long, so this name could reasonably be romanized as "Souseki," like the long "o" in "zouni". However, in reference books the standard romanization of this name is "Soseki".