Positivism might be self-evidently false. To the extent that Positivism attempts to say that there is no absolute truth mind independently, it cannot be itself true. We can use an ‘ontological’ type argument to demonstrate this. Suppose the positivist says that it is true that mind independent truth does not exist – is that ‘true’ mind independently? Suppose they bite the bullet and say that it is not true mind independently, but then we press further – isn’t it obvious that what makes it true that there is no mind independent truth has to be in some way mind independently grounded? If it is a mind-dependent truth which makes it the case that there is no mind-independent truth (that all truth is mind-dependent) then doesn’t that seem viciously circular? What ‘grounds’ our model-dependent realisms must be itself something which doesn’t result from those same models. It must belong to that which in-forms our models. Otherwise we must be coherentists rather than reliabilists. Ergo etc, and I would argue thus.
Upon reflection, I’m not even sure that positivism is meaningful to me at all, so I am a non-cognitivist with respect to positivism insofar as it suggests that truth can never be but mind dependent [model dependence entails mind dependence].