Verificationismism in the sense of the logical positivists is a theory of meaning. According to this theory, kowing the meaning of a statement p would amount to knowing the conditions under which it would be true and under which it would be false. (To give it a Bayesian slant, I like to widen this as “knowing what would be evidence for/against p). Is it this what you have in mind?
Verificationismism in this sense was used against postulating transcendent entities or state of affairs. Something is transcendent if it is beyond every possible experience. Therefore there is nothing which could verify of falsify facts about it. The logical positivists argued on the basis of verificationismism that statements about transcendent things (certain conceptions of God for example) are meaningless. Not false, but meaningless.
(Verificationismism lost a lot of popularity in the 1950s and 60s because there was very little progress in making the notion precise. Also, some apparently unverifiable theories (e.g. in astronomy) seemed to be perfectly meaningful. Whether those problems can be met I don’t know. Another point is that verificationismism was meant only as a condition of meaningfulness of so-called synthetic statements. Statements are synthetic iff their truth depends not only in their meaning. In contrast, the truth of “analytic” statements only depends on their meaning. The logical positivists assumed that logical and mathematical statements were analytic. Since verificationismism doesn’t apply to the meaning of those latter statements, it arguably isn’t a theory of meaning in the general sense.)
But, provided you speak about this notion, why would verificationismism lead to external world anti-realism? Because statements like “there is a tree in my garden” cannot be truly “verified”—because there might be no garden and no tree, and I might instead be deceived by a Cartesian demon?
For the “wider” conception mentioned above this wouldn’t be a problem I think. Having the visual impression of a tree is at least some evidence for there being a tree, even though there might be no tree. Then the statement is meaningful.
On the narrower conception and with a strict sense of “verification” the statement “There is a tree in my garden” would indeed be meaningless. Because there is apparently no experience which would verify or falsify it definitely. The same would be true about all other synthetic statements about the world. This wouldn’t mean that those statements are false and that external reality doesn’t exist: It would “only” mean thst those statements are meaningless. But here is the problem for this theory: It is obviously not meaningless to say that there is a tree in my garden.
One could argue that synthetic statements aren’t really about external reality: What we really mean is “If I were to check, my experiences would be as if there were a tree in what would seem to be my garden”. Then our ordinary language wouldn’t be meaningless. But this would be a highly revisionary proposal. We arguably don’t mean to say something like the above. We plausibly simply mean to assert the existence of a real tree in a real garden.
So I would argue that “evidence verificationismism” is much more plausible than “definite verification/falsification verificationismism”. The former would not lead to the conclusion that synthetic statements about the world are meaningless. Nor would it be in need of radical revisionism about the meaning of ordinary language.
But, provided you speak about this notion, why would verificationismism lead to external world anti-realism?
Anti-realism is not quite correct here, it’s more that claims about external reality are meaningless as opposed to false.
One could argue that synthetic statements aren’t really about external reality: What we really mean is “If I were to check, my experiences would be as if there were a tree in what would seem to be my garden”. Then our ordinary language wouldn’t be meaningless. But this would be a highly revisionary proposal. We arguably don’t mean to say something like the above. We plausibly simply mean to assert the existence of a real tree in a real garden.
I’m not making a claim about what people actually mean by the words they say. I’m saying that some interpretations of what people say happen to lack meaning. I agree that many people fervently believe in some form of external reality, I simply think that belief is meaningless, in the same way that a belief about where the electron “truly is” is meaningless.
Anti-realism is not quite correct here, it’s more that claims about external reality are meaningless as opposed to false.
This is semantics but I’d say what you’re describing fits the label “anti-realism” perfectly well. I wrote a post on Why Realists and Anti-Realists disagree. (It also mentions existence anti-realism briefly at the end.)
Verificationismism in the sense of the logical positivists is a theory of meaning. According to this theory, kowing the meaning of a statement p would amount to knowing the conditions under which it would be true and under which it would be false. (To give it a Bayesian slant, I like to widen this as “knowing what would be evidence for/against p). Is it this what you have in mind?
Verificationismism in this sense was used against postulating transcendent entities or state of affairs. Something is transcendent if it is beyond every possible experience. Therefore there is nothing which could verify of falsify facts about it. The logical positivists argued on the basis of verificationismism that statements about transcendent things (certain conceptions of God for example) are meaningless. Not false, but meaningless.
(Verificationismism lost a lot of popularity in the 1950s and 60s because there was very little progress in making the notion precise. Also, some apparently unverifiable theories (e.g. in astronomy) seemed to be perfectly meaningful. Whether those problems can be met I don’t know. Another point is that verificationismism was meant only as a condition of meaningfulness of so-called synthetic statements. Statements are synthetic iff their truth depends not only in their meaning. In contrast, the truth of “analytic” statements only depends on their meaning. The logical positivists assumed that logical and mathematical statements were analytic. Since verificationismism doesn’t apply to the meaning of those latter statements, it arguably isn’t a theory of meaning in the general sense.)
But, provided you speak about this notion, why would verificationismism lead to external world anti-realism? Because statements like “there is a tree in my garden” cannot be truly “verified”—because there might be no garden and no tree, and I might instead be deceived by a Cartesian demon?
For the “wider” conception mentioned above this wouldn’t be a problem I think. Having the visual impression of a tree is at least some evidence for there being a tree, even though there might be no tree. Then the statement is meaningful.
On the narrower conception and with a strict sense of “verification” the statement “There is a tree in my garden” would indeed be meaningless. Because there is apparently no experience which would verify or falsify it definitely. The same would be true about all other synthetic statements about the world. This wouldn’t mean that those statements are false and that external reality doesn’t exist: It would “only” mean thst those statements are meaningless. But here is the problem for this theory: It is obviously not meaningless to say that there is a tree in my garden.
One could argue that synthetic statements aren’t really about external reality: What we really mean is “If I were to check, my experiences would be as if there were a tree in what would seem to be my garden”. Then our ordinary language wouldn’t be meaningless. But this would be a highly revisionary proposal. We arguably don’t mean to say something like the above. We plausibly simply mean to assert the existence of a real tree in a real garden.
So I would argue that “evidence verificationismism” is much more plausible than “definite verification/falsification verificationismism”. The former would not lead to the conclusion that synthetic statements about the world are meaningless. Nor would it be in need of radical revisionism about the meaning of ordinary language.
Anti-realism is not quite correct here, it’s more that claims about external reality are meaningless as opposed to false.
I’m not making a claim about what people actually mean by the words they say. I’m saying that some interpretations of what people say happen to lack meaning. I agree that many people fervently believe in some form of external reality, I simply think that belief is meaningless, in the same way that a belief about where the electron “truly is” is meaningless.
This is semantics but I’d say what you’re describing fits the label “anti-realism” perfectly well. I wrote a post on Why Realists and Anti-Realists disagree. (It also mentions existence anti-realism briefly at the end.)
From my POV , you are external reality.