Common sense  Common sense is sound practical judgement concerning everyday matters, or a basic ability to perceive, understand, and judge that is shared by ("common to") nearly all people. The first type of common sense, good sense, can be described as "the knack for seeing things as they are, and doing things as they ought to be done". The second type is sometimes described as folk wisdom, "signifying unreflective knowledge not reliant on specialized training or deliberative thought." The two types are intertwined, as the person who has common sense is in touch with common-sense ideas, which emerge from the lived experiences of those commonsensical enough to perceive them. In a psychological context, Smedslund defines common sense as "the system of implications shared by the competent users of a language" and notes, "A proposition in a given context belongs to common sense if and only if all competent users of the language involved agree that the proposition in the given context is true and that its negation is false." The everyday understanding of common sense derives from historical philosophical discussion involving several European languages. Related terms in other languages include Latin ', Greek ('), and French "", but these are not straightforward translations in all contexts. Similarly in English, there are different shades of meaning, implying more or less education and wisdom: "good sense" is sometimes seen as equivalent to "common sense", and sometimes not. "Common sense" also has at least two specifically philosophical meanings. One is a capability of the animal soul (, ) proposed by Aristotle, which enables different individual senses to collectively perceive the characteristics of physical things such as movement and size, which all physical things have in different combinations, allowing people and other animals to distinguish and identify physical things. This common sense is distinct from basic sensory perception and from human rational thought, but cooperates with both. The second special use of the term is Roman-influenced and is used for the natural human sensitivity for other humans and the community. Just like the everyday meaning, both of these refer to a type of basic awareness and ability to judge that most people are expected to share naturally, even if they cannot explain why. All these meanings of "common sense", including the everyday ones, are interconnected in a complex history and have evolved during important political and philosophical debates in modern Western civilisation, notably concerning science, politics and economics. The interplay between the meanings has come to be particularly notable in English, as opposed to other western European languages, and the English term has become international. Since the Age of Enlightenment the term "common sense" has frequently been used for rhetorical effect, sometimes pejorative, and sometimes appealed to positively, as an authority.