The example above constitutes an analogy: The structure inherent to the sentences is used to explain a connection between different aspects. Although analogies are often used as a type of common-sense reasoning, to underline the understanding of the point one makes by comparing two objects or ideas, they are also useful for higher-order, deductive reasoning, for understanding abstract relations between objects. Consider that in the quote above Albert Einstein uses an analogy to explain (at the time) a new and complicated technology which nevertheless seems perfectly easy to understand because of the analogy.