Do opposites exist?

A simple question in essence, this; one for the pedants I guess.

To illustrate with an anecdote: the other day when discussing the unlikely relationship between a pair of my friends, I uttered the hoary old chestnut “well, opposites do attract.” My girlfriend, unsatisfied with this attempt to weasel, countered by suggesting that there are no true opposites anyway. In horror at this evasive response, I suggested that true white light (all colours of spectrum together) is opposite to total blackness (no light at all) - or more generally that absence is the opposite of presence. She was unsatisfied with this, insisting that the concept of absence by its very nature suggests the existence of presence and thus they are merely two sides of the same coin. “Phew”, I muttered. "Well what about… ", but I was stuck. If she was rejecting opposing pairs based on the fact that one member suggests the other, I was stuck.

So I thought that I’d throw it out to the teeming millions. What do you say guys - does ms kabbes have a point? Or is she missing the whole point of “opposite” as a concept? In short, do true opposites exist?

!!
She’s a wily one, kabbes. But I would think that the implication “no true opposites exist” is a bit nonsensical in her way of putting it…that is, if we define absence as the opposite of presence then surely it exists…by definition!

Perhaps that’s her hang up, that we’ve defined it. Now, IANAP(latonist ;)) but it would seem that if one accepts that there is an objective, external reality to the mind then even if we didn’t exist and weren’t here to define things absence would still be the opposite of presence. That is, though our definitions may seem abitrary, their arbitrary nature leads to a metaphysical truth (try that one on her!) for we may define A in terms of ~A or ~A in terms of A. In either case, one is the opposite of the other. If A is the opposite of ~A no matter haw we choose to define it then it would seem that there was something going on there.

But really, I would think, of course they are two sides of the same coin. That is, we can think about existence of something without having that thing exist (to wit: god, unicorns, American football). If we were to use her argument, then say “No unicorn exists” then one ends up existing because of it (since absence implies precense).

Hardly a satisfactory thing, IMO.

Cheers, kabbes.

Cheers ARL. Somehow I guessed that you would be along to have a pop at this one.

Being an impolite host however, I’m going to have to paraphrase you egregiously. As I understand it

suggests that one object being the opposite of the other is merely a definitional quirk. However

suggests that “oppositeness” is a fundamental thing - an inherent property that a pair of ideas can possess.

These two arguments are, in the absence of a better phrase, opposite to each other. Are A and ~A opposite because that is how we define them, because that is how we define “opposite” or because there really is some tangible idea of “opposite” that exists externally to A and ~A?

With regards to

I’d semantically like to point out that she isn’t saying that absence implies presence, more that absence suggests the possible existence of presence.

To use your above notation, A can’t be the opposite of ~A, since without A there is no ~A, so A and ~A are inherently related and therefore not true opposites. If A is to have an opposite it must be B, which is unrelated to A. But then B = ~A and so B is not an opposite either!

I see your argument forming - ~A does exist independently of A (after all this is an objective external reality). But is the nature of opposites objective and external? Can an opposite ever be anything other than a concept?

Hmm. I’m twisting my mind in circles here. Somebody else’s turn.

pan

kabbes

Ummm, maybe I’m being too literal minded here, but I have always thought that “Opposites Attract” was in some way a reference to magnetics, i.e. take two magnets, the rectangular variety illustrate this best, and the poles that attract one another are the opposite sides, the “North” of one is attracted to the “South” of the other.

I just assumed the saying was an alegory?

Taken in that context, then there are certainly opposites and they obviously attract.

-Doug

But dublos - in what way are the poles opposite, other than linguistically? Instead of “opposite” poles, we could have called them “complimentary” poles.

Is this really an opposite, in the same way that we say that light is opposite to dark? Why?

pan

Well, you were seeing what I was saying to some extent. The question is quickly becoming not whether opposites exist, but whether, if something exists does its opposite? Clearly, in the case of a unicorn, this cannot be the case. (As well, in the epistemology thread I tried to make a case that the idea of non-existence is impossible)

As such, IMO, are opposties.

We can run into all sorts of logical and applied problems with this, of course. Your black white definition is nice enough, I doubt few would quibble with it, but I have had an ongoing argument for years with a certian lady friend who is trying to convince me that color is there even if light isn’t. Not a chance, I say, light is color. We percieve color as light. Without light, there can be no color. But no, she says, the color is there (what causes the color), we just can’t see it. Sheesh.

In this sort of regard, with the A ~A notation, we could ask ourself if they are independant of each other in any way. Clearly they are. That is, though ~A may be defined in terms of A, A itself is defined. We would ask ourselves, could we start with ~A (call it B), and then define A (~B) in terms of it?

If this is the case then I would say that surely opposites do exist. However, this is where my non-existence cannot exist comes in. That is, it can exist as a concept (however shakey THAT would be), but not independantly. One can’t start with non-existence and “create” existence as its opposite…for there is nothing to create(and there are no opposites)! There is no “thing” that can create, definitions themselves don’t exist, etc etc. It is a dead end concept, one which must be nested as a simple negation of A (existence).

So, am I doing any better? [sub]If not, have a few pints of HSB or Harveys then get back to me![/sub]

dublos agreed, but there is no end to applying physical (from physics!) truth as metaphysical. :shrug: Those wacky scientists are always bugging out those wackier philosophers.

Just think what Kant would have thought of non-Euclidian geometry!

Agreed - a lot of this does seem to boil down to the existence of non-existence.

So does “absence” exist independently of “presence”? I’m not talking here about the absence of anything, but absence iteself, as a concept.

Define “absence” without using the concept of “presence” to do so.

pan

Sorry - that last question ("define absence without using the concept of “presence”) is for any others who might possibly be interested. ARL has already said that he regards non-existence without existence as being nonsense.

To him I guess the next question is whether the implication of this is that there are no true independent “opposites”?

pan

Indepent opposites. I’m adding that to my list of favorite oxymorons.

I mean duh. If there’s nothing for it to oppose, how the hell can it be an opposite?

As for the OP, tell your girlfriend that the two sides of every coin I have ever seen are opposite each other. Then at least the ball is back in her court.

Yes and No

:smiley:

I would say so. Just that all things do not necessarily have opposites. I’ve made the case for existence almost as best as I can (existence has no opposite; non-existence does not exist[sub]I don’t even like saying it, haha[/sub]).

It is possible that a case could be made for opposites not existing in fact, from the nominalist case where universals also do not exist in any way shpe or form. “Oppositeness” then, as a universal, doesn’t exist. How easy was that!

But if we accept universals as existing in some sense then we are indeed faced with a problem. Platonic: universals exist independant of the rest of stuff. “Whiteness” exists in and of itself, or oppositeness as the case may be. Never felt comfortable with that.
Realists might posit that universals only exist conceptually. “Whiteness” is there, but as a concept. A measurement, as Rand would pose. Their existence is contingent on existence of objective reality, and the objects contained therein. (not that platonists don’t believe in an objective reality, just that we aren’t getting the whole picture—Plato’s Forms, Kant’s noumenal reality, etc)

If we take universals as existing as concepts then surely oppositenes exists. The question now becomes, is this concept formation/abstraction valid? That is, can the concept of whiteness or oppositeness be said to be an unescapable conclusion in abstraction? Are this white envelope and my white coffee mug (forget the stains :p) really alike in some way or is the concept artificial (dependent on my personl abstraction)?

I’d say it is unartificial. But then, you say, didn’t you just switch from a realist argument to a platonic one (where universals exist)? Nah. The crucial distinction is that “whiteness” is a part of the object which is white. One cannot remove the whiteness from it and pass it around, much to the dismay of many acid heads I’m sure :wink:

So, then, are opposites always tautological/definitional in nature? Again, I would distinguish a “true” opposite from an artificial one.

A true opposite would be one where we may take either A or ~A as the starting point and then define the other, ~A or A, from it.

A false opposite would be purely artificial in nature, where we can only take A and get to ~A; were we to take ~A we could not get to A.

ALL OF THIS, of course, assumes the law of the excluded middle, and that things are either true or false, and that their opposites are then false or true. We run into some problems in mathematics here if we also go on to say that mathematics is true. Here is where the happy formalists come in and say math isn’t true or false, there is no true or false about math, only in math. But I’m not prepared to get into formalism Vs intuitionism Vs constuctionism, logical positivisism, mathematical platonism, blah blah blah. That is outside the scope of this book :smiley:
[sub]Enter spiritus mundi to destroy everything I’ve said[/sub]

But, the first sentence should read that I would say not; opposites do exist independently.

Yes, opposites exist, because anyone you ask can name an opposite of various concepts you might care to name.

An opposite is a concept such that the opposite of white is black, and that’s all there is to it. Any attempt to prove otherwise is a deconstructionist dismemberment of the language we use every day. An attempt to prove that opposites do not exist when any fool knows that they do means that the word “opposite” is being used with a different definition from the ordinary one and is therefore completely irrelevant from the real world.

Words have meanings, people.

Perhaps I’m coming at this the wrong way, but I have always taken it for granted that to define a pair of concepts as opposites, you must have a context in mind. Which then necessarily implies that opposites are related. If they weren’t they’d hardly be opposites, would they?
I mean, would you say “3.14” is the opposite of “cheese”? Of course not.

But two things may be opposites in one sense, as -1 and 1 are in the context of addition, however they are very similar in that they are both numbers with the same magnitude.

I guess the question then arises whether it is possible that a thing would have a “perfect” opposite. That is, can a concept have a corresponding concept which is opposite to it in any possible context. Off the top of my head, I would say “no”, since oppositeness in one context implies sameness in other contexts by the very definition of opposite (assuming we agree on that).

Forgive me for not checking back here very often.

arl - I like it. I’m gonna have to have a think.

matt_mcl - yes, yes, if you’re going to be so literal about it. But many words are in common use and yet have strict scientific or philosophical definitions that are contrary to that use.

A case in point - the current hot SDMB debate on race. From my understanding about that debate, as far as science can currently ascertain, “race” actually has no meaning. There are no “races”. And yet the word is in common use and everybody knows what it means.

There is nothing wrong in examining concepts and ideas to see where they lead. If we did not then many branches of maths and philosophy would not even exist. Often the initial thought is nowhere near as important as the journey that it takes us on.

pan

Well, actually, yes I want to get literal about it. If you get down to it, if we’re going to mix science/logic and language, nothing has any meaning. That’s because science/logic treats of the natural world and meaning, i.e. language, is a product of the human imagination. It can’t be pinned down except as a function of how people use the word. So if you start talking about a word’s meaning as being the meaning other than the one it actually has, you are being meaningless. And masturbation is fun, but we don’t do it in public.

Well, of course A suggets the existence of ~A. And of course they are “two sides of the same coin”. That’s what opposites are. To deny that two things are opposites because some relationship exists between them is silly; if you define “oppositeness” to be the abscence of a relationship, then by definition nothing is the opposite of anything else; if two things are opposites, then a relationship exists (oppositeness), so they aren’t opposites. To say that A is the opposite of B is not to say that A exists independently of B; it is to say that A is strictly dependent on B (or rather, the abscence of B).

kabbes, look at your hands. Press your palms together. Move them apart. You tell me, do opposites exist?

Seriously, they do exist – right down to the molecular level and below…

Tartaric acid, for instance, is optically active. This means that when you shine a beam of polarized light through it, the beam will be rotated in a certain direction. This is because the crystals of tartaric acid are all asymmetrical in the same way. You could say they are righthanded.

There is another form of tartaric acid, called racemic acid, which is optically inactive – it does not rotate light. The crystals of racemic acid are also asymmetrical, but not all in the same way. Instead, they are about equally righthanded and lefthanded. They are opposites.

If you separate the righthanded crystals from the lefthanded, you end up with both regular old tartaric acid, and a third form – levortartaric acid – which will rotate a beam of polarized light in exactly the opposite direction from the one in which it is twisted by tartaric acid.

nothamlet, so in essence what you are saying is that directions and orientations can have opposites. The first is a very narrow Euclidean-geometric point of view I’d have thought. The second has been dealt with by TheNerd (quite a neat synopsis I thought BTW): although my left hand is opposite to my right from within the orientation context, they are the same thing (pretty much) from a classification of body parts context. Reasonable conclusion? There are no absolute opposites.

However I think that despite matt’s best killjoy efforts (:p) I’ve profited from the thinking involved in this exercise. The viewpoints offered by arl, TheNerd, The Ryan et al have lead me to feel that ultimately it is all a question of context (probably best summaried by Dr Matrix!).

So my next question is: is a contextless objective reality possible, or does our conceptual reality always depend on context? But I think that question has already been covered in the epistimology thread. IIRC the answer is: reality? What’s that? :wink:

pan

True enough, it is all a question of context. Thing is though, take away the context and you’re on the slippery slope to solipsism… which, to use matt’sword, is, in the end, mastubation. And (I’m speaking from experience, here, ha) while jerking off may be safe, it sure is lonely.

It can be fun, though.

Cheers