tag:blogger.com,1999:blog-414482498098790205.post8760508358344992453..comments2019-04-10T00:37:11.085-06:00Comments on Questioning Software: Get excited about the negativeBen Simohttp://www.blogger.com/profile/11448600123169359955noreply@blogger.comBlogger3125tag:blogger.com,1999:blog-414482498098790205.post-41018597541279726032009-02-20T09:58:00.000-07:002009-02-20T09:58:00.000-07:00How do you test for 'sometimes Y'?:)How do you test for 'sometimes Y'?<BR/><BR/>:)Mark Tomlinsonhttps://www.blogger.com/profile/15930484383235071234noreply@blogger.comtag:blogger.com,1999:blog-414482498098790205.post-63785626850015454522009-02-20T09:44:00.000-07:002009-02-20T09:44:00.000-07:00Anonymous,Yes, it is a partial claim. And only tak...Anonymous,<BR/><BR/>Yes, it is a partial claim. And only take it as a partial claim. There is no claim that even implies vowel. There is no claim about cards with consonants on either side. <BR/><BR/>So with the claim "If a card has a vowel on one side, then it will have an even number on the other." ...<BR/><BR/>Turning over the A card can expose whether the opposite side contains the required even number. Just turning over the A and finding an even number would not prove the statement. It would only be an example of the statement being correct in a specific case.<BR/><BR/>Turning over 4 is not necessary to test the claim. It doesn't matter what's on the other side of the 4.<BR/><BR/>So what about the B and 7 cards?<BR/><BR/>What if the B or 7 card has a vowel on the other side?<BR/><BR/>What if the B or 7 card has a vowel on the side we can't see. Wouldn't that disprove the claim?<BR/><BR/><BR/>The tendency to want to turn over only A and 4 demonstrates confirmation bias. <BR/><BR/>BenBen Simohttps://www.blogger.com/profile/11448600123169359955noreply@blogger.comtag:blogger.com,1999:blog-414482498098790205.post-13617030825241560902009-02-20T09:17:00.000-07:002009-02-20T09:17:00.000-07:00I think the Wason example is wrong.The claim is: I...I think the Wason example is wrong.<BR/><BR/>The claim is: If a card has a vowel on one side, then it will have an even number on the other.<BR/><BR/>the claim does not say <B>anything</B> about what happens if the the card has a consonant on it - so the associated number on the card could be either even or odd.<BR/><BR/>So the test subjects have not got it wrong - turning over A and 4 would be enough to test the Wason claim because it is only a <I>partial</I> claim<BR/><BR/>In logic, the claim is an <I>implication</I>, i.e.:<BR/><BR/>vowel implies even<BR/><BR/>i.e. the number is even whenever there is a vowel, but the number could still be even with a consonant on the card<BR/><BR/>Howver it is a common logic fallacy to infer the reverse case<BR/><BR/>even implies vowel<BR/><BR/>For Wason to be right he would need to make an unambiguous claim, i.e.:<BR/><BR/>"If a card has a vowel on one side, then it will have an even number on the other. If a card has an even number on one side it will have vowel on the other"<BR/><BR/>In this case you <B>would</B> need to turn over all four cards to test the truth of the claimAnonymousnoreply@blogger.com