Every term for Intro I have a class or two on Aristotle, looking at change and causation. One of the things I do is not to jump into Aristotle -- if you just jump into Aristotle, students don't have any sense of how much thought is going into each of Aristotle's moves -- but instead simply ask students to tell me what change is. I'll do some guiding here and there -- pointing out when they are falling back into mere synonyms, asking them how something different can also be the same when it comes up (as it always does), asking them what they mean by 'time' when they argue that change is difference through time (as they always do at some point) -- and particularly note and direct the discussion toward things that are relevant to understanding Aristotle, without telling them that I am doing so. At some point I start transitioning to actually talking about Aristotle's account. They don't actually like the discussion. But they do get a better sense of the actual difficulties Aristotle is facing.
As I've already noted there are things that always, always, always come up if the discussion goes on long enough -- time, or difference of the same. One of the things I've found, though, is that students are actually pretty open to the idea that change might just be in the mind. 'Perception', 'thought', and 'perspective' regularly come up as parts of definitions students propose -- for instance, they might propose, as someone did today, that change is different insights or perceptions of the same thing, or they might say that it is a perception of difference in something thought to be the same, or what is perceived by the senses, or a measurement of difference, all of which came up today.
At one point, I noted that several of the suggestions seemed to require that change be purely mental, and asked how many people thought that was true. About half the class said they did, with the other half saying that such an idea was absurd. One can't take that too seriously! There is always a portion of the class that is responding not with their own views but the view that they think at the moment I am looking for, or, indeed, responding in an attempt to find something, anything, that will make me stop asking them what change is. But it comes up every term. And every term there are at least a few students who argue for it quite intensely. And having lots of experience with it coming up, I think it actually arises in a given conversation from more than one cause. It comes up so often because several things allow for an easy transition to it, so if any of these things come up, the idea that change is all in the mind is likely to come up.
(1) The questions, "What is change?" and "How do we know what change is?", are difficult for people to distinguish, particularly in a group conversation. But, of course, knowing things is mental.
(2) Trying to explain change in terms of time makes it very difficult not to treat change as a mental phenomenon of some kind. We do not directly sense time, but only know it by measurement (in a broad sense of the word), and there are at least some reasons to think of time as perspective-dependent. But, of course, in English we naturally tend to talk about change in terms of time, and they have all heard discussions of particular changes that treat time as the fundamental thing, so any tendency to think of time in mental terms carries over to change.
(3) Perception is an obvious way you can have differences of the same without contradiction.
(4) One kind of change is mental change. Once that comes into view, it is surprisingly easy to assimilate physical change to mental change -- mental change is, in a sense, the change we know best.
(5) The Parmenidean notion, that what is and is known is not changing, has more traction than one might expect, in part, I think, because change is clearly not a thing, and they often take what is not a thing to be a mental construct rather than something known to exist.
(6) Pop Buddhist ideas encourage it.
(5) and (6) don't come up all the time, but they tend to be the causes that lead most consistently to students arguing for the position at length rather than (as they do with most of the other suggestions they make) jumping to something else at the first hint of a problem.
