Emotivism

Emotivism is a meta-ethical view that claims that ethical sentences do not express propositions but emotional attitudes. Hence, it is colloquially known as the hurrah/boo theory. Influenced by the growth of analytic philosophy and logical positivism in the 20th century, the theory was stated vividly by A. J. Ayer in his 1936 book Language, Truth and Logic, but its development owes more to C. L. Stevenson.

Emotivism can be considered a form of non-cognitivism or expressivism. It stands in opposition to other forms of non-cognitivism (such as quasi-realism and universal prescriptivism), as well as to all forms of cognitivism (including both moral realism and ethical subjectivism).

In the 1950s, emotivism appeared in a modified form in the universal prescriptivism of R. M. Hare.

Emotivism reached prominence in the early 20th century, but it was born centuries earlier. In 1710, George Berkeley wrote that language in general often serves to inspire feelings as well as communicate ideas. Decades later, David Hume espoused ideas similar to Stevenson's later ones. In his 1751 book An Enquiry Concerning the Principles of Morals, Hume considered morality to be related to fact but "determined by sentiment":

In moral deliberations we must be acquainted beforehand with all the objects, and all their relations to each other; and from a comparison of the whole, fix our choice or approbation. … While we are ignorant whether a man were aggressor or not, how can we determine whether the person who killed him be criminal or innocent? But after every circumstance, every relation is known, the understanding has no further room to operate, nor any object on which it could employ itself. The approbation or blame which then ensues, cannot be the work of the judgement, but of the heart; and is not a speculative proposition or affirmation, but an active feeling or sentiment.

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