Sorts of mistakes

For one reason or another I find the following example by Elisabeth Anscombe in her Intention intriguing. It’s about a shopper and a detective. Maybe, you are also fascinated by it, so here it is: A man is going around with a shopping list that says what he is to buy. A detective follows him and makes a list of what the man buys. I think that we can say at least three things about this example, which are related, though.
1) Following Anscombe, we can say that the shopper’s list describes his intention, or alternatively it is an order that the shopper executes (maybe his wife made the list). Even if the list is an order, we can see it as an expression of the shopper’s intention, for it describes what he wants to do when going around. However, the detective observes the shopper, so for him his list is a record of what the shopper has bought. We can say that the shopper’s list contains his first-person perspective on what he is doing, while the detective’s list describes what the shopper does from a third-person perspective.
2) Let’s suppose now that the shopper or the detective makes a mistake. By mistake the shopper buys butter instead of margarine, as his list says. Or by mistake the detective notes down “butter”, for the shopper bought margarine. What is the difference? Since the shopper’s list is meant to direct his actions, he made a mistake in performance by buying butter, since he didn’t perform what he intended to do. However, the detective’s list is meant to record what the shopper did and by writing “butter” instead of “margarine” his list has become inaccurate. Here we see two sorts of mistakes that you can make when acting: mistakes in performance and inaccuracy. In the first case the list is good but the mistake is in what the shopper did. In the second case, the list is not true to the facts.
3) However, when we look at the shopper only, there are more kinds of mistakes he can make, so that his list and what he buys diverge:
a) There is a mistake in the construction of the list: One or more items on the list cannot be bought in the town where the man is shopping. They don’t sell cowpeas there, for instance. Here we have another sort of mistake you can make: A mistake of judgment
b) The shopper changes his mind because in the end he thinks that butter tastes better than margarine in the cake he is going to bake. Here there is no mistake in the proper sense, except then that shopper behaved against what the list said to buy or that he misjudged what should be on the list. Actually, this is also a kind of mistake of judgment
c) The shopper simply doesn’t buy what is on the list, for instance because he forgot to buy an item. We can call this mistake “carelessness”, or what you like. 

Especially the mistakes given under 3) are not unrelated to what I wrote in my blog last week, as Schwenkler makes clear. Let’s look at the ways a person can fail to perform an intention:
- A person fails to act because s/he cannot act (3a). This is in line with the soldier in my example last week who couldn’t clench his teeth because his teeth were false.
- A person changes his/her intention or expresses an opposing intention (3b). This is in line with a soldier who refuses to obey an order or a commander who gives an opposing order.
- A person simply fails or is failing to act (3c). This is in line with a soldier who fails to act as ordered. 

There are mistakes and mistakes, but making mistakes is what humans do, anyway. 

Sources
- G.E.M. Anscombe, Intention. Oxford: Basil Blackwell, 1976 (my edition); § 32.
- Schwenkler, John, Anscombe’s Intention. A Guide. Oxford: Oxford University Press, 2019; pp. 111-114.