History & Philosophy of Psychology essay
Consider Locke 's distinction between ideas of primary qualities and ideas of secondary qualities . On what basis did Locke draw this distinction and what difficulties does it encounter ? Outline briefly Berkeley 's views on Locke 's distinction between primary and secondary qualities . Critically comment on Berkeley 's position here The idea that the properties of physical objects can be divided into two classes is one that was popular among the pioneers of the physical sciences in the 17th century . The doctrine found its most eloquent expression in the writings of John Locke
The idea that the properties of physical objects can be divided into two classes is one that was popular among the pioneers of the physical sciences in the 17th century . The doctrine found its most eloquent expression in the writings of John Locke
, who gave the distinction in terms of primary and secondary qualities
Locke divides the qualities of physical objects into two classes primary qualities and secondary qualities
Primary qualities , Locke says , are those properties of an object that are inseparable from its body . This includes of mass , solidity extension , figure , motion , and number . This is not to claim that those qualities in an object cannot be modified (plainly they can ) but rather than it is not possible for an object to be without mass , solidity shape , extension , size . Secondary qualities , on the other hand , are nothing in the object itself but the powers of its primary qualities to produce sensations in us - that is , colour , taste , sound and so on . Our sensations of primary qualities are very similar to those qualities themselves : we experience the mass of an apple in our hand as being something that forces the apple towards the ground unless we exert force in keeping it up . We experience the shape of the apple as it is . This is not to say , of course , that our perceptions of primary qualities cannot be false - plainly we may look at a table and think it round when it is in fact elliptical - but rather that our perception of the primary qualities is of something that is essentially the same as what causes those perceptions . This is not the case with secondary qualities . Our perceptions of secondary qualities are qualitatively different to the qualities themselves . The taste of an apple is caused by the nature of the chemicals in its flesh interacting with our tongue . We don 't however , perceive it as such - we perceive only the taste . When we look at the apple in hand we perceive it as green . Our perception is caused by the arrangement of the molecules in the surface of the apple and their effect upon what light is absorbed and what reflected by the surface . Nevertheless we do not perceive the arrangement of the molecules : we perceive the colour . Moreover if we take away the source of illumination then we cannot sensibly say that the apple still has colour - but the arrangement of the molecules (which is , after all , a primary quality of the apple ) remains unchanged . Consequently , Locke argued , while its primary qualities are inseparable from an object , its secondary qualities seem not to be
One immediate objection is worth discussing here . It might simply be denied that the apple ceases to...