Edouard Machery at the Experiments in Philosophy blog writes about a study he conducted with Zalla that found that people with Aspergers syndrome were deficient when it came to identifying purely instrumental desires and the actions resulting from them as intentional actions. but to understand all that we have to understand the concept of purely instrumental desire. This is best done with the free-cup and extra-dollar cases that Machery has constructed to illustrate this phenomenon:
The Free-Cup Case
Joe was feeling quite dehydrated, so he stopped by the local smoothie shop to buy the largest sized drink available. Before ordering, the cashier told him that if he bought a Mega-Sized Smoothie he would get it in a special commemorative cup. Joe replied, ‘I don’t care about a commemorative cup, I just want the biggest smoothie you have.’ Sure enough, Joe received the Mega-Sized Smoothie in a commemorative cup. Did Joe intentionally obtain the commemorative cup?
The Extra-Dollar Case
Joe was feeling quite dehydrated, so he stopped by the local smoothie shop to buy the largest sized drink available. Before ordering, the cashier told him that the Mega-Sized Smoothies were now one dollar more than they used to be. Joe replied, ‘I don’t care if I have to pay one dollar more, I just want the biggest smoothie you have.’ Sure enough, Joe received the Mega-Sized Smoothie and paid one dollar more for it. Did Joe intentionally pay one dollar more?
You surely think that paying an extra dollar was intentional, while getting the commemorative cup was not. So do most people.
Machery likes to analyze the different actions involved in getting a smoothie in terms of their causal structure as well as their valence for the subject (positive valence means actively desired; while negatively or neutrally valanced meaning that one would not like that action to take place normally, but might indulge in if it is instrumental and an intermediate step towards archiving of an ultimate desire.
Thus, in the extra dollar case quenching thirst is the ultimate desire, buying a smoothie an instrumental desire, while shelling an extra dollar though negatively valued is still a purely instrumental desire as it is requisite for fulfilling the ultimate desire. Thus, normal people would consider paying the extra-dollar as intentional as it was due to an action due to a (purely) instrumental desire.
In the free-cup case, again the ultimate desire is to quench the thirst, the instrumental desire is to buy a smoothie, and the free cup that one gets is neither desired ultimately or as (purely) instrumentally as a menas towards an end. In simple words it is not desired at all and I would like to name it as co-incidental desire as opposed to instrumental desire (because having a special edition cup may still have some valence for joe, though he doesn’t actively desire it. Normal as well as Aspergers people deemed getting the free cup as non-intentional.
Where the Aspergics differed was in the extra dollar case. They still thought that paying the extra dollar was non-intentional and Eduoard theorizes that this may be due to inability of those with ASD to consider acts which are merely means towards an end as having an intentional quality.
I might not agree with the specific theorizing of Machery, but I agree that people with ASD have deficits in intentionality and I have been shouting this from rooftops for quite some time now. I also assert that Schizophrenics have too much concept of intentionality. I would not be surprised if a schizotypal, schizophrenic population was given these above two scenarios and it was found that a co-incidental desire like getting a free-cup was also deemed to be an intentional actions. One could come up with strange rationalizations and explanations and believe that though he just wanted to quench his thirst he went to this vendor only because he also wanted a free cup. This would be an extreme case of Magical Thinking, but I wont be surprised to see schizophrenics attributing more intentionality than is done by normal people. I hope someone does the experiment and lets me know! Edouard are you listening?
EDOUARD MACHERY (2008). The Folk Concept of Intentional Action: Philosophical and Experimental Issues Mind & Language, 23 (2), 165-189 DOI: 10.1111/j.1468-0017.2007.00336.x