[soxocx]

> Illusion involving a hidden thumb confounds capuchin and squirrel monkeys for the same reason as humans – it misdirects the expected outcomes of actions they can carry out.

To be fair. As a human I would state you expect it to be a trick (a very easy one to spot in this case) and you can easily infer that the coin just _drops_ into the hand it was to start with. It does not feel that it has anything todo with what actions you can carry out. The coin is either grabbed by the non-coin hand or not, it depends on the magician, right?

[amelius]

Really after seeing the trick I could only conclude the coin could be in either hand.

[mannykannot]

True, but I don't think we can conclude that opposable thumbs correlate with a reduced capacity for deductive logic.

[mannykannot]

As a human, I would expect a trick given the article's title, or maybe in a context where it seems some sort of test or demonstration is being given, but then, I have seen these sort of things before.

The trick works on humans, even when they know they are watching someone performing an illusion, if the performer can distract their attention at the right moment.

[eightnoneone]

As a monkey, I want treats.