Unamuno's philosophy was not systematic but rather a negation of all systems and an affirmation of faith "in itself." He developed intellectually under the influence of rationalism and positivism, but during his youth he wrote articles that clearly show his sympathy for socialism and his great concern for the situation in which he found Spain at the time. An important concept for Unamuno was "intrahistoria". He thought that history could best be understood by looking at the small histories of anonymous people, rather than by focusing on major events such as wars and political pacts. Some authors relativize the importance of "intrahistoria" in his thinking. Those authors say that more than a clear concept is an ambiguous metaphor. The term first appears in the essay "En torno al casticismo" (1895), but Unamuno leaves it soon.