VivaHedone

Generally, we know that what is inside us exists, and anything else is uncertain. We know that we exist. We know that the sensations exist, as we experience them.

We do not know what the sensations are, and whether they reflect reality or not (that is to say, assuming that an objective reality exists). (However, it seems wise to assume, for the purposes of life, that the swensations do reflect reality.) Therefore we cannot know, for instance, whether trees exist.

I think that we can probably know that logic exists, though I'm not sure.

Is there anything else we can truly know exists? For instance, what about language? Could we just be imagining it?

eh

If we are imagining it, then it at least exists in the mind. So we can only be certain that what we think truely exists.

John Page

I know that trees exist, the question is "What is a tree?". Also, are your trees the same trees as mine?

Cheers, John

sweep

define existence-

if we imagine something does that mean that it does not exist?

Demosthenes

Also what suppose you have a sophisticated computer that's simulating a hummingbird at a cellular level. It behaves exactly like another hummingbird made out of flesh but it's within the computer's memory. So does the virtual bird exist just like the organic bird? In other words is both of the birds equally "real"?

What if you link the simulated hummingbird's brain to a robotic body indistingushable from an organic one, it flys around, seeks out flowers just as the regular one do. If you show it to somebody else and he can't tell the virtual bird apart from the organic bird, doesn't it implies that there's really no difference between whether one is a pattern of information within a computer or embodied in a fleshy body? And then our common sense regarding "existence" of various entities is flawed and requires revision?

John Page

1. Existence is a word used to denote something that "is".
2. If we imagine something that means the something exists in our imagination.

John Page

Not "just like".
The birds are equally real but they comprise different substances.
Clearly there is a difference, whether it matters is a question of circumstance, for example, whether you want non-simulated flowers to be pollinated.
Our common sense can be deceived, so one needs to be careful. No two things are absolutely identical, (for otherwise we could not tell them apart and there would only appear to be one), but some things are more different than others.

Cheers, John

John Galt, Jr.

VivaHedone,

I am a bit puzzled by your remarks. For example, you say Who is the 'We' you are talking about? If I am included among those in the 'we' group, are you saying that I, John Galt, Jr., know that my sensations exist, but that I don't (ever) know that my sensations reflect reality?

John Galt, Jr.

Demosthenes

John Galt Jr:

I think he's trying to say that although we may perceive our sensations to be some reflection of the reality, we don't know the extent that our sensations actually reflect reality as it really is rather than the interpretation created by our brains.

John Page: yes, they're not "just like" i meant to say that the two hummingbirds, though existing in two different mediums are at least functionally alike, meaning that it flies, walks, buzzes like a hummingbird, thus it is a indeed a hummingbird.

Does something that exists within a software environment can possess a reality that is real to us?

Something that only interacts in the computer won't affect us at all, if we were to hook it up to a robotic extension then it'll certainly start influencing the physical world and thus have we given it a physical basis where it can then stand equal with other physical manifestations?

Please tell me if I'm not making too much sense and I'll try to reword it better.

sweep

and something that is, has meaning only to the extent that something is not. In other words something is, that which it is not.