{"id":8102,"date":"2014-02-28T05:04:55","date_gmt":"2014-02-28T05:04:55","guid":{"rendered":"https:\/\/maverickphilosopher.blog\/index.php\/2014\/02\/28\/three-more-putative-instances-of-valid-is-ought-inferences\/"},"modified":"2014-02-28T05:04:55","modified_gmt":"2014-02-28T05:04:55","slug":"three-more-putative-instances-of-valid-is-ought-inferences","status":"publish","type":"post","link":"https:\/\/maverickphilosopher.blog\/index.php\/2014\/02\/28\/three-more-putative-instances-of-valid-is-ought-inferences\/","title":{"rendered":"Three More Putative Instances of Valid Is-Ought Inferences"},"content":{"rendered":"

I thank Tully Borland for pushing the discussion in this fascinating direction.<\/span><\/p>\n

A<\/span><\/p>\n

Affirming the Consequent is an invalid argument form.<\/span>
Ergo<\/span>
One ought not (it is obligatory that one not) give arguments having that form.<\/span><\/p>\n

B<\/span><\/p>\n

Modus Ponens is valid<\/span>
Ergo<\/span>
One may (it is permissible to) give arguments having that form.<\/span><\/p>\n

C<\/span><\/p>\n

Correct deductive reasoning is in every instance truth-preserving.<\/span>
Ergo<\/span>
One ought to reason correctly as far as possible.<\/span><\/p>\n

An argument form is valid<\/em> just in case  no (actual or possible) argument of that form has true premises and a false conclusion. An argument form is invalid<\/em> just in case some (actual or possible) argument of that form has true premises and a false conclusion.  Deductive reasoning is correct<\/em> just in case it proceeds in accordance with a valid argument form.  'Just in case' is but a stylistic variant of 'if and only if.'<\/span><\/p>\n

Now given these explanations of key terms, it seems  that validity, invalidity, and correctness are purely factual, and thus purely non-normative, properties of arguments\/reasonings.  If so, how the devil do we get to the conclusions of the three arguments above?<\/span><\/p>\n

View One<\/em>:  We don't.  A, B, and C are each illicit is-ought slides.  <\/span><\/p>\n

View Two<\/em>:  Each of the above arguments is valid.  Each of the key terms in the premises is normatively loaded from the proverbial 'git-go,' in addition to bearing a descriptive load..  Therefore, there is no illict slide.  The move is from the normative to the normative.  Validity, invalidity, and correctness can be defined only in terms of truth and falsity which are normative notions.<\/span><\/p>\n

View Three<\/em>:  We have no compelling reason to prefer one of the foregoing views to the other.  Each can be argued for and each can be argued against.  Thus spoke the Aporetician.<\/span><\/p>\n

\nRelated articles<\/legend>\n
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\"\"<\/a>Syntactic Versus Semantic Validity<\/a><\/div>\n
\"\"<\/a>Truth and Normativity<\/a><\/div>\n
\"\"<\/a>From the Laws of Logic to the Existence of God<\/a><\/div>\n
\"\"<\/a>The Stromboli Puzzle Revisited<\/a><\/div>\n<\/div>\n<\/fieldset>\n","protected":false},"excerpt":{"rendered":"

I thank Tully Borland for pushing the discussion in this fascinating direction. A Affirming the Consequent is an invalid argument form.ErgoOne ought not (it is obligatory that one not) give arguments having that form. B Modus Ponens is validErgoOne may (it is permissible to) give arguments having that form. C Correct deductive reasoning is in … Continue reading “Three More Putative Instances of Valid Is-Ought Inferences”<\/span><\/a><\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[21,248,108],"tags":[],"class_list":["post-8102","post","type-post","status-publish","format-standard","hentry","category-aporetics","category-ethics-of-belief","category-logica-docens"],"_links":{"self":[{"href":"https:\/\/maverickphilosopher.blog\/index.php\/wp-json\/wp\/v2\/posts\/8102","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/maverickphilosopher.blog\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/maverickphilosopher.blog\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/maverickphilosopher.blog\/index.php\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/maverickphilosopher.blog\/index.php\/wp-json\/wp\/v2\/comments?post=8102"}],"version-history":[{"count":0,"href":"https:\/\/maverickphilosopher.blog\/index.php\/wp-json\/wp\/v2\/posts\/8102\/revisions"}],"wp:attachment":[{"href":"https:\/\/maverickphilosopher.blog\/index.php\/wp-json\/wp\/v2\/media?parent=8102"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/maverickphilosopher.blog\/index.php\/wp-json\/wp\/v2\/categories?post=8102"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/maverickphilosopher.blog\/index.php\/wp-json\/wp\/v2\/tags?post=8102"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}