Argumentative Essay On Twin Earth

Twin Earth

The Traditional view of meaning was formed long ago throughout the middle ages, resting on two core assumptions . First that being able to understanding the meaning of a term is only a reflection of the person physiological state since grasping a concept is an act done in the head. A physiological state is a state of the mind in relation to certain memories and physiological habits. The second assumption dictates that intension (A concept in the head) fixes extension (A reference to something in the world). In other words two terms cannot differ in extension and have the same intention. This perspective on meaning has not gone without criticism though as Putnam describes frege and carnap’s “rebellion” against the traditional

Next Putnam says that if a person from earth visits twin earth the first thought of the travelers would believe that water holds the same meaning on both Earths, until the true molecular nature of the two “waters” is discovered, and vice versa. Putnam then goes to say “One should not say ‘On twin earth the meaning of the word water is XYZ’ unless, possibly, the fact that XYZ is water”. From here two interpretations are possible, the first being putnams conclusion that XYZ is not water which is critical to the remainder of his critique. The second is that XYZ is a form of water and that both XYZ and H2O carry the same intention. In a way Putnam shows that the word water is and isn't H2O or XYZ but referring to the set of properties that it presents in the physical world creating a concept, While H2O and XYZ are referring to the molecular nature of the actual compounds. From there Putnam comes to the idea that the extension of “water” on Earth is different from the extension of “water” on Twin Earth. Later Putnam ads that before the discovery of water’s chemical structure in 1750 a person on Earth was still referring to

The first being that “water” is consistent in its meaning, but relative in the idea it puts forth. Therefore Earth and Twin Earth’s “water” shares the same meaning but on Twin Earth its represents the idea of XYZ and on Earth the idea of H2O. The second Theory he offers is that “water” is constant in the idea put forth but relative in meaning. This provides the answer that Twin Earth “water is not Earth “water”, In fact that Twin Earth doesn't even contain “water”. Putnam prefered his second theory because he believes natural kinds are based in dialect, thus its a term that identifies the same object in all possible world or a rigid