On December 2, 2015, Frank Bruni of the New York Times put out an op-ed column titled "Anyone but Ted Cruz" which essentially blasted the presidential candidate as unfit for office. Bruni's op-ed ends:
...it’s the fruit of a combative style and consuming solipsism that would make him an insufferable, unendurable president.
Harsh words—and somewhat confusing words, too. Bruni's use of solipsism sent readers scrambling to the dictionary for a definition.
Solipsism is defined in our Online Dictionary as both "a theory holding that the self can know nothing but its own modifications and that the self is the only existent thing," and "extreme egocentrism." It's clear that Bruni was using the second definition in his column.
Solipsism comes to us ultimately from the Latin words solus and ipse, which mean "alone" and "self," respectively, and was popular in philosophy, where the nature of knowledge and the self is a popular topic of discourse. A translation of one such philosopher's work (Kant's The Metaphysic of Ethics) is what gave us our first use of the English solipsism: "The aggregate of the appetites (which easily admit of being brought into a very tolerable system, and whereof the gratification is then one’s own happiness) make up and compose what is called selfishness or solipsism." The philosophical meaning touches not just on existentialism, but egocentrism as well, and in time, solipsism gained the extended sense we see in use today. It's a word that's been used in recent articles about a wide variety of people and things, from punk singer Glenn Danzig, to the movie "Toy Story 3," to soccer player Cristiano Ronaldo.
It's also a favorite of pundits, who like to use it of a broad variety of political candidates. In just the last month, solipsism (or its related adjective, solipsistic) has been used of Donald Trump, Bernie Sanders, Democrats in general, and, of course, Ted Cruz.