logic1

Are logical arguments evidence?

It is said that an argument will convince a reasonable man, and a proof will convince even an unreasonable man. So why do so-called atheists insist upon evidence? In a previous discussion, a claim was made that logical arguments are not evidence. Here I want to unpick that comment and see if we can find a way of thinking about the relationship between evidence and logical arguments that is helpful.

First I want to draw a distinction between two different types of evidence. First there is physical-evidence. This would be material stuff, such as bullet shells, exit wounds, DNA, photographs, lab results, etc. All of these would be available, either directly or indirectly to the five senses.

I take it that it was this type of evidence that was meant by the claim logical arguments are not evidence – that is, physical-evidence. Such as an arrowhead in cave can be said to be evidence for human habitation of that cave. Or that a shivering of a body can be said to be evidence it is cold.

What is troubling is that if physical-evidence is a necessary for knowledge, then we should know nothing of moral truths, aesthetic values, and meta-physical intuitions. Yet surly we do know that torturing babies is wrong, open graves are macabre, waterfalls are sublime, that the past is objective and other minds do exist. The Achilles heal of this particular epistemological theory is it is self-referentially incoherent. If its reasonable, then its unreasonable by its own merits. For no physical evidence is able to to reveal that evidence is required for reasonable belief. If it could be rationally affirmed and were true, then the Christian would be in an awkward position, for a further implication would be there is no hope for reasonable belief in non-physical entities. In fact the criteria, if adopted, would rule out the possibility of attaining reasonable belief in non-physical entities before any discussion or debate began.

There must therefore be something terribly wrong then with the criteria. Which is why I’d like to draw our attention to another type of evidence called argument-evidence. Evidence is broadly speaking that which lends support to a proposition or claim. Argument-evidence is any reason given for believing something is true or false. That is not to say that all argument-evidence is good evidence. That is just to say that arguments can count as evidence, in that they too give support for believing some proposition or claim. There can of course be counter-evidence that could dissuade belief.

For those not inclined to accept this distinction I have drawn between and physical-evidence and argument-evidence, and those who disagree with me that arguments can count as evidence, it will be useful to consider the following.

Physical evidence doesn’t speak. That is to say, all physical-evidence passes through the filter of an interpretative lens, and, perhaps unnoticed by the advocate, acquires certain meaning that was not intrinsic to the object or event itself. More colloquially, material objects have no voice to tell you what they signify. Everything is interpreted by a person who brings with them additional premises from their world view and store of experiences.

We have all gone through what its like to say one thing, and for two people to hear totally different things. A fossil will tell a paleontologist one thing. The same fossil will tell the next paleontologist another thing – sometimes even used to support mutually exclusive theories. Yet if physical-evidence was all there was available for investigation, how is it then that disparate theories can arise over the same object or event?

What happens is that somewhere between an objects discovery and its interpretation additional premises are added. These premises combine to form arguments. One hopes of course that these arguments are logical. Different premises given by different perspectives lead to different conclusions. Thus, in a way, all evidence is argument-evidence, for the physical-evidence, if left to itself, remains silent and tells us nothing.

103 replies
« Older Comments
  1. Stuart
    Stuart says:

    Joe,

    I think I'm missing your twisted humor. Are you deliberately playing the fool? For instance;

    Joe [quoting Allan Guth]: One possibility would be a quantum origin

    Stuart: A quantum… what?

    Joe: origin. Or is it reading comprehension that fails you?

    Or is it you who is failing to comprehend that a quantum explanation of the origin of the universe, is still an origin of the universe.

    Again,

    Stuart: I can agree that its speculative. As is all science to some degree. But there is no reason to think that the Borde-Guth-Vilenkin theorem does not give great support to the idea that the universe began to exist a finite time ago.

    Joe: Do all hypotheses give credence to certain notions?

    No, of course not. But the theorem of Borde, Guth and Vilenkin is not some idle hypothesis. Vilenkin says "with the proof now in…"

    Again,

    check down 2 paragraphs: … [quote from Vilenkin]

    What does this have to do with the beginning of the universe? That is the premise we were arguing for. These logical problems can be dealt with later, or now if you'd care to elaborate them. This attempt at derailing the whole argument in one foul sweep was pathetic. The only way I can charitably construe it is as a joke.

  2. Joe
    Joe says:

    Or is it you who is failing to comprehend that a quantum explanation of the origin of the universe, is still an origin of the universe.

    And this is a problem for me how? Effectively even in this near 0-point energy field, it is a "universe", ie "all that exists".

    Stuart: I can agree that its speculative. As is all science to some degree. But there is no reason to think that the Borde-Guth-Vilenkin theorem does not give great support to the idea that the universe began to exist a finite time ago.

    Joe: Do all hypotheses give credence to certain notions?

    No, of course not. But the theorem of Borde, Guth and Vilenkin is not some idle hypothesis. Vilenkin says “with the proof now in…”

    It IS a hypothesis, since it is unevidenced and based on the incomplete inflationary theory. We don't even know the nature of the singularity from which the Big Bang arose.

    Again,

    check down 2 paragraphs: … [quote from Vilenkin]

    What does this have to do with the beginning of the universe? That is the premise we were arguing for. These logical problems can be dealt with later, or now if you’d care to elaborate them. This attempt at derailing the whole argument in one foul sweep was pathetic. The only way I can charitably construe it is as a joke.

    Nice of you to play the "saint" again. Except it's that thinly disguised and pitiful attempt at an insult. What does that have to do with the beginning of the universe? What does ONE model have to do with whether it's been established there IS a beginning of the universe? NOTHING. You admit there are other models which have no such problems, such as the Aquirre-Gratton model. What's your point? You continue to point at one POSSIBLE model to claim SEE? THE UNIVERSE BEGAN! When in fact all you can say is that THUS FAR, IT'S POSSIBLE IF THE BVG IS CORRECT, THERE WAS AN "ORIGIN".

    This STILL doesn't help your case since EVEN IF THERE WAS A BEGINNING, it STILL doesn't provide ANY justification for your "therefore god" drivel.

  3. Stuart
    Stuart says:

    Joe,

    I'm going to close the comments as it looks as if we're at an impasse. From my perspective all you are doing playing the immovable skeptic, repeating old objections and capitalizing words as if it helps the points you're making. I know you'll view things differently, but I think I've answered all your objections and the comment thread is already far too long. Thank you for participating, and let me recommend you get yourself a gravitar for future discussions.

Trackbacks & Pingbacks

« Older Comments

Comments are closed.