The funny thing about us is we don't pay attention to small changes as much as we do big ones. For example, no one gets fat overnight. We wake up each day a tiny bit heavier than before and maybe after a couple of years you look in the mirror and say “damn, where did all this fat come from... I used to be in shape”. My family owns a cabin in the mountains and we would go there a couple times a year. In my mind, the cabin and surrounding mountains were always the same, but in reality it was always changing. Each spring the river would wash the banks a different way after each thaw, the trees would be a little taller, and the weeds would be in a different place than the last time.
I think the analogy you're making has its uses, brillo_pad. But let me ask-- out of curiosity-- doesn't the perceived scale of the change (small, big) have a lot to do with the
nature of the change? I'm not sure that putting on a few pounds is of the same order of change as something that radically alters personality-- certain kinds of brain damage, for instance. Hence the difference between major and minor changes.
And changes involve
something changing...
So my point? Every time you encounter someone, in reality we meet a new person. Now you may have “known” or” know” this person, but this idea is based on our memories. Look at what happens in the case where someone changes drastically. The way they behave dosen't conform to our memories, so it confuses us. The person has the same body and face, but does not act the same. Is it the same person? The answer is no. The same goes for us. We are not the same person we were five minutes ago or even after looking at the period at the end of this sentence. Small changes go unnoticed. When you meet someone after an event like my friend's, the drastic change shocks you and you have to accept the “new” person for what they are today. Same goes for meeting an old acquantince. You small talk to get the basic information/changes out of the way and then accept the person, changes and all. Or not if they turn out to have turned into a jerk.
This reminds me of the discussions one finds in 18th and 19th Century philosophy-- and later, among certain early 20th Century philosophers-- about ideas of continuity and contiguity.
It sounds a bit as if you're confusing the map of the person (who you thought the person to be, your perceptions of the person) with the person's existence in-and-of-itself. (Insofar as it can be perceived, one's existence provides one with an identity in a strictly philosophical/epistemological sense. "To be is to be perceived," as the man said-- and being
always comes first. Being human implies that an individual has some unique "being" on a molecular, cellular, neurochemical level-- individual consciousness and subjectivity, among other things. While consciousness seems to change over time, there's always something
behind that, a thinking, feeling "Self". And for a thing or person to be perceived by someone is for that thing or person to be perceived as "not-me" by the observer.)
Basically, I think being a jerk-- or whatver-- is an attribute or perception, rather than an essence. We think of some attributes as identities, and they function as such, sometimes. But they aren't the thing-itself, or the person-him/herself. And the changes you perceive can only take place in relation to the person and your perception of the person... but the perception wouldn't exist without the person.
We sometimes notice that a person or thing changes as a result of time, i.e. we assume that changes occur
to something or to our
perception of or in our
thinking about something. But whenever changes occur (provided that they're not too significant, too radical), we view the thing that's changed as having something like an essential "sameness" throughout the change-- as having an identity or cluster of identities, the details of which have changed. But this isn't to say that the thing or person who's changed is no longer the "same" thing or person. Even if your behavior differs from day-to-day or significantly alters after an interval of several years, it's still
your behavior. I'm not going to assume that you're not you-- as awkward as that phrasing is. I'll just assume that you've changed, or you're having a bad day, or you're happy, or traumatized, or whatever.
Similarly, we notice that we change over time precisely because we experience those changes. But we don't question that the changes are happening to
us; on some fundamental level "we" exist, and that's how we become aware of the changes.
To put this another way, to use an analogy: We can observe a particle decaying, but as we observe the decay, we understand that the changes are happening
to a given particle. Just because the particle decays, we don't assume there are multiple or different particles at each microsecond of decay. And if you've been observing or recording a particle for a while, and I've seen what you're measuring but leave for a bit, then I come back, look at the data, and say, "Gee, this isn't the same particle you've been measuring for however long," you'd be correct in pointing out that it
is the same particle, that decay is part of a particle's "life", that I'm wrong.
Of course, particles can be combined with other particles to create composite particles or broken down into smaller units or even annihilated, but in these cases, we usually say that the original particle has "ceased to be itself", i.e. it's not what it was, it's no longer the thing we were observing. It's
changed in a pretty basic way. It's either part of something else, has become something else, or is nonexistent in these instances. Its structure-- and therefore its nature or essence-- isn't what it was, or else the particle has become part of an aggregate or composite-- which also implies a change in function, thereby changing both what the particle "means" and, in a manner of speaking, what it "is"-- at least until the composite is broken down.
(Being a jerk would be an attribute of or value-judgment about the person you used to like, for example. Either you didn't notice the attribute before, or the person took on the attributes or behaviors that you think belong to someone who fits the category "jerk", or you were conned by the person. But the attribute and the changes are properties of or occur to something or someone who has some "self", some essence, some continued and sequential identity
in time and space-- even to the perceiver.
(If you decide I'm a wonderful person but meet me and decide that I'm a jerk, you'll be thinking, "AlphonseVanWorden is a jerk", by which you mean, "Alphonse has jerklike qualities or behaves in a manner I find indicative of his being a jerk or belonging in the jerk-category." My being a jerk isn't something that's fixed or a given-- after all, someone else might not perceive me as a jerk, or maybe I'm having a bad day when you meet me, or whatever. But these statements are predicated on my existing or having existed. No Alphonse, no Alphonse's jerk-status. And if you liked me at one time and your perception of me later changed, that's not really saying that there is no underlying "Alphonse".
(This isn't to say that Alphonse doesn't/I don't change over time. But even that change is predicated on
my existing. Kill me and cut me into pieces, and phrases such as "Alphonse's hand" or "Alphonse's leg" or "Alphonse's brain" have meaning only in relation to the Alphonse-who-is-no-more. But while I'm alive and completely intact, those parts are components of the whole that
is me. Some parts you can live without; others are more essential to one's existence. Existence, pure and simple: That's one kind of identity-- one that's pretty much the foundation of all other possible identities and perceptions, including not-being, non-existence.)
The brain-damage thing is a little dicier. We worry about, contemplate, and study the relationship between mind/self and body. Do certain types of brain damage cause changes to a person such that the person "isn't the same" in essence? If you have severe retrograde amnesia, are you the "same" person you were before the condition's onset? In some ways, yes, you are. In other ways, maybe not. But notice that these are different questions from that of someone's changing over time. The situations involve something more radical than losing a hand or a foot, gaining weight, or getting older. And the questions involve not only perception, but essence. And some of the questions about brain damage, mental illness, and personality can't be easily answered at present.
We could compare this with what happens to particles, and we could wonder if there are some changes to a person that alter "who" the person "is" in a more fundamental way than the changes that naturally occur to a person over a lifetime.
We ask other questions about essence and identity, too. And we can perform certain types of meta-thinking about these matters. (Critical theory, some types of mystical and metaphysical thought, and quantum mechanical models are good examples of this sort of meta-thinking.) But on some level, we're basically wired to make certain day-to-day assumptions about essence and existence. We notice that this is me, this is not-me. And we assume that some clusters of not-me have a "discrete and separate" identity (this is a person, a dog, a rock-- the words come after the fact, but the perception/awareness is there pretty early, if our brains are healthy), that they are discrete entities.
This kind of goes back to gillsing's point:
Yup, he's still the Matt-identity. And if he during his coma was 'infected' with an alien brain-bug which read his memories, reactivated his brain/body and then didn't feel like doing athletics and wasn't overly interested in school and felt like talking more, then you'd still consider him to be Matt, because you wouldn't know that his changes were induced by an alien mind. Thus he would keep being the Matt-identity.
I'd modify gillsing's language a bit and say that Matt still has and would have the Matt-identity
for you. Matt's status-as-Matt (his essential Mattness, if you'll pardon me) after the alien brain-bug takes him over would be a little harder to ascertain-- and would probably have a lot to do with the
nature of the bug. Mutualist symbiote, commensalist symbiote, or parasite...
Such is the soul in the body: this world is like her little turf of grass, and the heaven o'er our heads, like her looking-glass, only gives us a miserable knowledge of the small compass of our prison. - Bosola, in John Webster's The Duchess of Malfi