The scientific method can and is applied to psychology and sociology, but the social science disciplines do not quite lend themselves to the rigor of the natural sciences. In any case, the latter certainly doesn't prevent quackery in chemistry or biology or astronomy or geology - e.g., creation science.
the social science disciplines do not quite lend themselves to the rigor of the natural sciences.
Sociology and Psychology could become sciences if the 'rigor of the natural sciences' was applied. But funding in the universities would probably dry up in that case. So they exist in the twilight zone somewhere between real science and superstition and folklore. Physics and chemistry and biology existed there at one time.
Unfortunately, what could be true sciences of sociology and psychology are corrupted by politics and economics.
So I repeat they are not really science. What I object to is they try to present themselves as such (kind of like the MSM claiming they are unbiased). At least economists admit that their avocation is not a science (because they no one would believe them if they tried).
BTW, 'creation science' can't even be elevated to the level of quackery.