Certo! Eccolo!

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<title>Il ragionamento condizionale</title>

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<p align="center" style="margin-top: 30; margin-bottom: 30"><font face="Tahoma" size="4">Il
ragionamento condizionale</font></p>
<p align="left"><font face="Tahoma" size="3">Premessa: <span style="mso-fareast-font-family: Times New Roman; mso-ansi-language: IT; mso-fareast-language: IT; mso-bidi-language: AR-SA">La
logica e l'algebra di Boole</span></font></p>
<p align="left"><font face="Tahoma">Logica: disciplina che studia le regole di
ragionamento messe in atto dai soggetti (ideali). Assume il punto di vista
normativo, sintattico, computazionale. Ad essa attinge ma si contrappone la
Psicologia del pensiero, interessata maggiormente ai processi di ragionamento
sottesi alla &quot;scatola nera&quot;</font><font face="Tahoma">.</font></p>
<p align="left"><span style="mso-fareast-font-family: Times New Roman; mso-ansi-language: IT; mso-fareast-language: IT; mso-bidi-language: AR-SA"><font face="Tahoma" size="3">p,
q, r <span style="font-size:12.0pt;font-family:&quot;Times New Roman&quot;;
mso-fareast-font-family:&quot;Times New Roman&quot;;mso-ansi-language:IT;mso-fareast-language:
IT;mso-bidi-language:AR-SA">→ </span><span style="font-size: 12.0pt; mso-fareast-font-family: Times New Roman; mso-ansi-language: IT; mso-fareast-language: IT; mso-bidi-language: AR-SA">Variabili
proposizionali dove p=(V, F) </span></font></span></p>


<font face="Tahoma">Connettivi logici </font><span style="mso-fareast-font-family: Times New Roman; mso-ansi-language: IT; mso-fareast-language: IT; mso-bidi-language: AR-SA"><font face="Tahoma" size="3"><span style="font-size:12.0pt;font-family:&quot;Times New Roman&quot;;
mso-fareast-font-family:&quot;Times New Roman&quot;;mso-ansi-language:IT;mso-fareast-language:
IT;mso-bidi-language:AR-SA">→</span></font></span><font face="Tahoma">
and, or, if...then, etc...</font></p>




<font face="Tahoma">Ragionamento condizionale: poste due premesse (ad es,
&quot;p&quot; e &quot;q&quot, assegno a ciascuna di esse un valore di verità
(1 o 0) e le unisco con il connettivo if...then (condizionale, il cui simbolo è
</font><span style="mso-fareast-font-family: Times New Roman; mso-ansi-language: IT; mso-fareast-language: IT; mso-bidi-language: AR-SA"><font face="Tahoma" size="3"><span style="font-size:12.0pt;font-family:&quot;Times New Roman&quot;;
mso-fareast-font-family:&quot;Times New Roman&quot;;mso-ansi-language:IT;mso-fareast-language:
IT;mso-bidi-language:AR-SA">→</span></font></span><font face="Tahoma">).

Tabella di contingenza del ragionamento condizionale:</font></p>
<div align="left">
<table border="1" width="159" height="139">
<tr>
<td width="28" height="24" align="center">p</td>
<td width="29" height="24" align="center">q</td>
<td width="80" height="24" align="center"></td>
</tr>
<tr>
<td width="28" height="103" align="center">V

V

F

F</td>
<td width="29" height="103" align="center">V

F

V

F</td>
<td width="80" height="103">
<p align="center">V

F

V

V</td>
</tr>
</table>
</div>


<font face="Tahoma">Secondo il quale, analizzando le varie contingenze:</font></p>


<font face="Tahoma">p(V) </font><span style="mso-fareast-font-family: Times New Roman; mso-ansi-language: IT; mso-fareast-language: IT; mso-bidi-language: AR-SA"><font face="Tahoma" size="3"><span style="font-size:12.0pt;font-family:&quot;Times New Roman&quot;;
mso-fareast-font-family:&quot;Times New Roman&quot;;mso-ansi-language:IT;mso-fareast-language:
IT;mso-bidi-language:AR-SA">→ </span></font><font face="Tahoma"><span style="font-size: 12.0pt; mso-fareast-font-family: Times New Roman; mso-ansi-language: IT; mso-fareast-language: IT; mso-bidi-language: AR-SA"><font size="3">q</font></span><font size="3"><span style="font-size: 12.0pt; mso-fareast-font-family: Times New Roman; mso-ansi-language: IT; mso-fareast-language: IT; mso-bidi-language: AR-SA">(V)
Modus ponens (p deve essere necessariamente vera perchè </span></font></font><span style="font-size: 12.0pt; mso-fareast-font-family: Times New Roman; mso-ansi-language: IT; mso-fareast-language: IT; mso-bidi-language: AR-SA"><font size="3" face="Tahoma">p(V)
</font></span><font face="Tahoma" size="3"><span style="font-size:12.0pt;font-family:&quot;Times New Roman&quot;;
mso-fareast-font-family:&quot;Times New Roman&quot;;mso-ansi-language:IT;mso-fareast-language:
IT;mso-bidi-language:AR-SA">→</span></font><span style="font-size:12.0pt;font-family:&quot;Times New Roman&quot;;
mso-fareast-font-family:&quot;Times New Roman&quot;;mso-ansi-language:IT;mso-fareast-language:
IT;mso-bidi-language:AR-SA"><font face="Tahoma" size="3"> </font></span><font size="3" face="Tahoma"><span style="font-size: 12.0pt">q(F)</span><span style="font-size: 12.0pt; mso-fareast-font-family: Times New Roman; mso-ansi-language: IT; mso-fareast-language: IT; mso-bidi-language: AR-SA">
è Falsa);</span></font></span></p>


<font size="3" face="Tahoma"><span style="font-size: 12.0pt; mso-fareast-font-family: Times New Roman; mso-ansi-language: IT; mso-fareast-language: IT; mso-bidi-language: AR-SA">q(F)</span></font><span style="font-size: 12.0pt; font-family: Times New Roman; mso-fareast-font-family: Times New Roman; mso-ansi-language: IT; mso-fareast-language: IT; mso-bidi-language: AR-SA"><font face="Tahoma" size="3">
</font></span><span style="mso-fareast-font-family: Times New Roman; mso-ansi-language: IT; mso-fareast-language: IT; mso-bidi-language: AR-SA"><font face="Tahoma" size="3"><span style="font-size:12.0pt;font-family:&quot;Times New Roman&quot;;
mso-fareast-font-family:&quot;Times New Roman&quot;;mso-ansi-language:IT;mso-fareast-language:
IT;mso-bidi-language:AR-SA">→</span></font></span><span style="mso-fareast-font-family: Times New Roman; mso-ansi-language: IT; mso-fareast-language: IT; mso-bidi-language: AR-SA"><span style="font-size:12.0pt;font-family:&quot;Times New Roman&quot;;
mso-fareast-font-family:&quot;Times New Roman&quot;;mso-ansi-language:IT;mso-fareast-language:
IT;mso-bidi-language:AR-SA"><font face="Tahoma" size="3"> </font></span><span style="font-size: 12.0pt; mso-fareast-font-family: Times New Roman; mso-ansi-language: IT; mso-fareast-language: IT; mso-bidi-language: AR-SA"><font size="3" face="Tahoma">p(F)
Modus tollens (perchè, secondo la II contingenza, p(V) </font></span><font face="Tahoma" size="3"><span style="font-size:12.0pt;font-family:&quot;Times New Roman&quot;;
mso-fareast-font-family:&quot;Times New Roman&quot;;mso-ansi-language:IT;mso-fareast-language:
IT;mso-bidi-language:AR-SA">→</span></font><span style="font-size:12.0pt;font-family:&quot;Times New Roman&quot;;
mso-fareast-font-family:&quot;Times New Roman&quot;;mso-ansi-language:IT;mso-fareast-language:
IT;mso-bidi-language:AR-SA"><font face="Tahoma" size="3"> </font></span><font size="3" face="Tahoma"><span style="font-size: 12.0pt">q(F)</span><span style="font-size: 12.0pt; mso-fareast-font-family: Times New Roman; mso-ansi-language: IT; mso-fareast-language: IT; mso-bidi-language: AR-SA">
è Falsa);</span></font></span></p>


<font size="3" face="Tahoma"><span style="font-size: 12.0pt; mso-fareast-font-family: Times New Roman; mso-ansi-language: IT; mso-fareast-language: IT; mso-bidi-language: AR-SA">p(F)
</span></font><span style="mso-fareast-font-family: Times New Roman; mso-ansi-language: IT; mso-fareast-language: IT; mso-bidi-language: AR-SA"><font face="Tahoma" size="3"><span style="font-size:12.0pt;font-family:&quot;Times New Roman&quot;;
mso-fareast-font-family:&quot;Times New Roman&quot;;mso-ansi-language:IT;mso-fareast-language:
IT;mso-bidi-language:AR-SA">→</span></font><span style="font-size:12.0pt;font-family:&quot;Times New Roman&quot;;
mso-fareast-font-family:&quot;Times New Roman&quot;;mso-ansi-language:IT;mso-fareast-language:
IT;mso-bidi-language:AR-SA"><font face="Tahoma" size="3"> </font></span><font size="3" face="Tahoma"><span style="font-size: 12.0pt; mso-fareast-font-family: Times New Roman; mso-ansi-language: IT; mso-fareast-language: IT; mso-bidi-language: AR-SA">q(F,V)
Nulla ne consegue (sospensione del giudizio), se affermassi che p(F) </span></font><font face="Tahoma" size="3"><span style="font-size:12.0pt;font-family:&quot;Times New Roman&quot;;
mso-fareast-font-family:&quot;Times New Roman&quot;;mso-ansi-language:IT;mso-fareast-language:
IT;mso-bidi-language:AR-SA">→</span></font><font size="3" face="Tahoma"><span style="font-size: 12.0pt; mso-fareast-font-family: Times New Roman; mso-ansi-language: IT; mso-fareast-language: IT; mso-bidi-language: AR-SA">
q(F) incorrerei nella fallacia della NEGAZIONE DELL'ANTECEDENTE;</span></font></span></p>


<font size="3" face="Tahoma"><span style="font-size: 12.0pt; mso-fareast-font-family: Times New Roman; mso-ansi-language: IT; mso-fareast-language: IT; mso-bidi-language: AR-SA">q(V)
</span></font><span style="mso-fareast-font-family: Times New Roman; mso-ansi-language: IT; mso-fareast-language: IT; mso-bidi-language: AR-SA"><font face="Tahoma" size="3"><span style="font-size:12.0pt;font-family:&quot;Times New Roman&quot;;
mso-fareast-font-family:&quot;Times New Roman&quot;;mso-ansi-language:IT;mso-fareast-language:
IT;mso-bidi-language:AR-SA">→</span></font><span style="font-size:12.0pt;font-family:&quot;Times New Roman&quot;;
mso-fareast-font-family:&quot;Times New Roman&quot;;mso-ansi-language:IT;mso-fareast-language:
IT;mso-bidi-language:AR-SA"><font face="Tahoma" size="3"> </font></span><font size="3" face="Tahoma"><span style="font-size: 12.0pt; mso-fareast-font-family: Times New Roman; mso-ansi-language: IT; mso-fareast-language: IT; mso-bidi-language: AR-SA">p(V,F)
Nulla ne consegue (sospensione del giudizio), se affermassi che q(V) </span></font><font face="Tahoma" size="3"><span style="font-size:12.0pt;font-family:&quot;Times New Roman&quot;;
mso-fareast-font-family:&quot;Times New Roman&quot;;mso-ansi-language:IT;mso-fareast-language:
IT;mso-bidi-language:AR-SA">→</span></font><font size="3" face="Tahoma"><span style="font-size: 12.0pt; mso-fareast-font-family: Times New Roman; mso-ansi-language: IT; mso-fareast-language: IT; mso-bidi-language: AR-SA">
p(V) incorrerei nella fallacia dell'AFFERMAZIONE DEL CONSEGUENTE.</span></font></span></p>




<font face="Tahoma">Ma perchè gli esseri umani non ragionano come la logica ha
supposto? Ovvero, perchè commettono fallacie?</font></p>


<font face="Tahoma">Fattori:</font></p>
<ul>[*]<font face="Tahoma">relazione causale fra</font><font face="Tahoma"> le
variabili proposizionali;</font>[*]<font face="Tahoma">credibilità delle proposizioni stesse;</font>[*]<font face="Tahoma">familiarità con il problema;</font>[*]<font face="Tahoma">altri: scarsa attenzione, scarsa motivazione, etc...

</font>[/list]


<font face="Tahoma">Wason ha confermato ulteriormente questo aspetto con il
problema delle quattro carte (Wason selection task), il quale viene risolto solo
da circa il 10% di soggetti:</font></p>




<font face="Tahoma" size="2">Controllare, girando max 2 carte, la regola secondo
la quale dietro a un asso c'è un 2.

</font>
</p>




[img]CartaA.jpg[/img]
[img]Carta2.jpg[/img]
[img]cartak.jpg[/img]
[img]carta7.jpg[/img]
</p>


<p style="margin-top: 0"><font face="Tahoma" size="2">
p
non
-p
q
non-q</font>
</p>


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