Mark asked:

I've come up against an idea that won't budge. Perhaps you will see my error, or perhaps you can
direct me to relevant literature. Here goes:

I've come to think it is impossible to imagine a universe in which I do not exist. Because in order to
perceive of that imaginary place, I must have some sense data of it. And in order for there to be
sense data, there must be some existing thing that senses.

It's as simple as the logical contradiction involved in imagining yourself being in a room in which you
do not exist. You "look around", but you are not there. But what is doing the looking? Is it possible to
imagine that nothing there exists and yet looking happens? I don't think so. I think we just ignore the
fact that we must "be" in this universe-that-doesn't-contain-us, and sidestep the contradiction. I think
we must postulate our existence in that universe in order to perceive it, and in doing so we violate the
premise of our non-existence.

Even though it is subject to the whim of imagination, I cannot so bend the rules of logic to imagine
that I both am and am not in the same place. I cannot imagine what that would be like.

I used to think (just this morning!) that it was a simple thing to imagine a universe in which I didn't
exist. Now I think that to the extent that I can imagine it, I violate the premise of my non-existence.

============

First, you are confusing two senses of "imagine". One is "perceive" and one is "think of". Obviously
you can think of a universe in which you don't exist... you're doing it above. Second, you can think of
being in a room, the furniture in it, etc., etc., with as much detail as you want... but you still don't have
to be visualizingthat room. So the dilemma you're having is that you can't conceive of visualizing
something without a viewpoint from which to visualize it, and that implies an observer. Ok fine.
Perhaps it does. However, first, that observer doesn't have to be you as you actually are. For
example, you could visualize a room from 1/4 inch above the floor, or from the viewpoint of an ant,
right? Now, how could that be you? So just whose existence are you "postulating" there? No
particular existence; it's just that in order to visualize, you need a reference point. You're postulating a
point of view, not any particular observer. Of course, you could object that your observer is utilizing
visible light instead of x-rays or sonar, and so that implies that observer is restricted by what you can
conceive of... ok, fine... and...? So in order to visualize something you must do it in ways that are
limited to what you can conceive of. Well, I'll agree to that. But I still don't see that you're then
restricting it to you,as such.

Further, what is the point of this question? Clearly you can conceive of a universe in which you don't
exist; as I say, you're doing it just fine above. So what do you want? You want to be able to visualize
a room in another universe, one in which you don't exist... withouthaving a viewpoint from which to
visualize it? But then what would "visualize" mean? Surely the act of visualizing itself implies a
viewpoint? I suppose you might want to visualize from all possibleviewpoints at once, and you're
disappointed that you cannot. Well that certainly is a human limitation, and as such it is a human
viewpoint that we must utilize to visualize a room, or whatever. So in that very general sense you're
correct. I guess you're going to have to find a computer to do your non-human visualizing for you.

Steven Ravett Brown

Your problem is exactly Kant's problem. So here you have a focus at once for your endeavours. Now
I or another respondent could write at length on what you want to know, without soon getting to the
bottom of it. But assuming that it is an issue which really troubles you, I would suggest that you
sidestep all second-hand accounts and go straight for the Critique of Pure Reason.It is by no means
as hard as often made out; in fact, on my view it is a model case of sober philosophical writing and
certainly no more difficult to read than Bertrand Russell (who would not be pleased to hear me say
this!). Nonetheless you may get stuck because there are inevitable historical associations to absorb,
and to help you overcome these hurdles, let me recommend Sebastian Gardner's book on the
Critique in the Routledge Guidebooks. Alternatively, Brian Magee has written a fine book on his own
travails as a youth, very much of the same kind as your's; and how later his discovery of Kant
changed his outlook on life and philosophy. This might be even better for you, given the similarities.
The book is called Confessions of a Philosopher.Wishing you the best and that your argosy proves a
happy and challenging adventure!

I now have a request to make of you. Your question is quite indiscriminate in its usage of the term
'sense data'. You're not to blame for it; it is a common fault. All the more reason to fix it! What you call
'sense data' are, in fact, sensa,which are the impressions received and processed by your nervous
system, brain, perception, cognition etc. Sense data, on the contrary, are unformedstream of
impressions which do not make it to any of these processing units. In other words: we are bombarded
every second of time by millions of 'sense data', but what we then actually see, hear, touch etc. are
'sensa'; the 'data' are the rejects. I wish this elementary distinction was more readily observed. In my
reading of the literature I have observed massive amounts of confusion arising precisely from its
non-observance. So you can help! Make the point whenever you're asked to write or speak on the
subject.

Jürgen Lawrenz

Sydney

I get your point.

But in one aspect I don't believe you. I think you can very well imagine what people are saying about
you when you're not there. That's a favourite pastime. Now serious: imagining a universe without
yourself can be done in two ways.

1. Focusing on things that don't concern your personal presence (like gossip)

2. Focusing on things that need input of yourself

The second option acquires your presence. So it is impossible to imagine it without yourself.

It's like trying to imagine yourself doing an exam without being there. I don't know the definition of it,
but to me that seems a 'contradictio in terminus'

Henk Tuten

I think I see what your getting at — kind of like Sartre's claim that you can't imagine your own funeral
because your already there? I guess most of the problem revolves around how we imagine these
situations. Visually imagining is hard because you can't escape your own first-person perspective —
like in Sartre's example — there is a sense in which your there. But suppose we just represent the
situation linguistically: we tell a story, about a world in which all that exist are gorillas that listen to
classical music (which they've come up with) and eat purple asparagus. Now, I certainly don't exist in
that world — I've stipulated that — but I have succeeded in representing that state of affairs but the
simple method of Kripkean specification — (after Saul Kripke) whereby we simply stipulate what's
going on that world and in doing so we represent that world. As long as that world is not inconsistent
(i.e there are no logical contradictions) then that world is logically possible. I suppose that if we try
and visually imagine that world that I always represent it from my viewpoint but like i've suggested,
representation doesn't stop with our visual modalities.

Rich Woodward

The short answer is, I think, that sense data (if there are such things) don't have to be any particular
person's sense data. It is the Idealist's mistake that all sense data must be his own sense data.
Bishop Berkeley was (as might be expected) particularly bedevilled by this error.

Ken Stern