Another post here made the point that it is necessary to guide empiricism with strong theoretical frameworks. Those strong theoretical frameworks are missing in psychology/neuroscience, because it is a very very new field tacking something very very complicated. We have weak theories, and thus empirical findings may fail to replicate for differences we do not measure (season? time of day? menstruation? obesity? coffee? as examples of things that might not be measured, or is not practical to include into statistical models due to df) and so on. But this is not to say that there has not been progress. There has been lots of progress, and theories are becoming better, ever so slowly. but we build on converging methods spanning basic neuroscience of individual neurons or local networks to MRI studies of macro phenomenology.
In the end, I think of myself more as a cartographer or explorer, much like those that set sail across the sea knowing little about what will be found, BUT DOCUMENTING IT in their naval logs and reports, so that one day those observations can be put together and build the world map. That is why open neuroscience is critical to our field.
Of course there's no dishonesty. And to be bad would require what you do to be science in the first place. From my perspective (physicist), "science" is applied too broadly. What you do isn't useless or unimportant. I just struggle to square it with "science" in any meaningful sense. That's probably not a popular opinion, but whatever: I stand by it.
From one point of view that just proves your point more, from another, less. If placebo effect is tenuous then all else equal that’s a good sign for the rest of medicine… but in fact lots of medicine is tenuous. The landmark “Most Published Research Findings Are False” was looking at medical findings iirc.
We can't predict human behavior because our science is simply not advanced enough. I think once we have as strong an understanding of biology as we do something like say, physics or mathematics, we'll find it significantly easier to predict human behavior.
Or put another way, I don't think we can't predict human behavior because humans are "special", but because we're actually kind dumb on a cosmic scale.
It is irreproducibility in a few fields. Most notably, nutrition, psychology, and economics.
These are all fields which study humans. The study of humans is far more fraught with bias and ideology. Humans are also independent decision making agents and behave in a way that atoms do not.