PART 1

>> The mind is not part of nature?

>Nope. It's a theoretical construct with no empirically measurable properties. https://en.wikipedia.org/wiki/Mind%E2%80%93body_problem : "The mind–body problem is a philosophical problem concerning the relationship between thought and consciousness in the human mind and body."
This is a problem because there's no obvious connection between the mind and everyday reality.

Now, I finally understand where you are coming from, but I believe it is misconceived. While the mind is indeed a complex construct, cognitive psychology does not treat it as separate from empirical reality. Modern cognitive science and psychology link the mind's activities to physical processes in the brain, measurable through tools like neuroimaging (fMRI, PET scans), electroencephalograms (EEGs), and other methods that correlate mental states with brain activity. These techniques allow researchers to observe brain regions involved in memory, perception, and decision-making, offering empirical support for the study of mental processes. While the "mind-body problem" is a philosophical issue, cognitive psychology and neuroscience work from a materialist perspective that views the mind as arising from brain activity, making it empirically approachable.

I agree that early psychology was not scientific. Psychological research has evolved significantly since René Descartes' dualism separated the mind and body as distinct entities. Yes, this view dominated early thought, yes, Fuck Freud. Freud was not a scientist. The beginning of empirical psychology actually started in the early 20th century with 'Behaviorism', led by figures like John B. Watson and B.F. Skinner, focusing strictly on observable behaviors and rejecting the study of the mind, rooted in the desire to make psychology as rigorous and objective as the natural sciences. Behaviorists argued that psychology should limit itself to measurable, external actions, drawing on the idea that only behaviors that can be observed and quantified objectively should and can be studied scientifically. They argued that the mind could not be directly observed, and thus would lead to subjective and unscientific conclusions.

For Watson and Skinner, all behavior was the result of conditioning by the environment, either treating the mind as a black box that transforms inputs and outputs, or by denying a mind at all. But by the mid-20th century the limitations of behaviorism became extremely clear. For example, although Skinner tried to explain how children learn language through reinforcement, famously Chomsky showed that theory to the door [1]. Other fields also began to highlight the inadequacies of behaviorism. The rise of computers in the 1950s and 1960s offered a powerful analogy for human cognition. Scientists began to view the mind as an information-processing system, much like a computer, capable of storing, retrieving, and manipulating information. This shift led to the emergence of cognitive psychology, which treated the mind as a complex system with its own internal rules and processes, much of which could be scientifically studied through indirect methods like reaction times, error rates, and neuroimaging. For instance, studies in memory and perception revealed that people often reconstruct memories or interpret stimuli based on prior knowledge, something behaviorism could not explain since it denied the role of internal representations. Furthermore, cognitive psychologists like George Miller and Ulric Neisser demonstrated that mental processes could be objectively studied. Miller's work on the capacity of short-term memory (his famous "7±2" paper) and Neisser's Cognitive Psychology (1967), which consolidated the field, showed that cognition involved quantifiable processes like attention, memory, and problem-solving. Another example: While most cognitive psychology of memory (for example) based theorizing on objective measures of memory (hits misses, false alarms and correct rejections under different experimental conditions, others began probing subjective reports of their memory experience along with responding yes or no when asked if they seen a stimuli before in a memory experiment, asking questions like, "How sure are you on a Likert scale", or "how visual was the memory?". These kinds of questions rely on subjective reports, but contained information with empirical external validity, like objective memory accuracy, objective increases in BOLD response within regions which from lesion studies in rats and non-human primates (and in humans with damage to those regions. Indeed the brain of infamous amnesic HM was in the freezer behind my lab a decade ago.

>> As to Popper, there is no singular definition of science ...
>This is not true. Falsifiability and empirical evidence are part of the universally accepted definition of science. This is why mathematics, as important as it is to science, is not itself accepted as a science -- like psychology, it doesn't address empirical reality.
>Carl Sagan, quoted from "The baloney detection kit" (https://www.themarginalian.org/2014/01/03/baloney-detection-...): "Always ask whether the hypothesis can be, at least in principle, falsiﬁed. Propositions that are untestable, unfalsiﬁable, are not worth much. Consider the grand idea that our Universe and everything in it is just an elementary particle—an electron, say—in a much bigger Cosmos. But if we can never acquire information from outside our Universe, is not the idea incapable of disproof? You must be able to check assertions out. Inveterate skeptics must be given the chance to follow your reasoning, to duplicate your experiments and see if they get the same result."

Popper’s criterion of falsifiability has been a cornerstone of scientific philosophy and it is important because it helps distinguish science from pseudoscience. Popper's take down of Freud makes him legend in my book. As I said earlier, Fuck Freud. However, it is important to also recognize the falsifiability is not always straightforward. Complex systems like those in biology do not easily lend themselves to clean falsification, theories are often probabilistic and deal with multifactorial causes rather than strict one to one cause-and-effect relationships. Consider a theory about how stress affects memory: testing such a theory might involve controlled experiments, but it’s often difficult to fully falsify because human and animal behavior is influenced by many variables. Yet, the predictive accuracy of models can be assessed through statistical analysis, allowing for refinement and testing of these theories without outright falsification in a Popperian sense. Moreover, science is also about confirmation within paradigms [2], and Popper's notion of falsification is often idealized beyond what is actually achievable. Broader Definitions of Science today includes concepts like cumulative evidence and refinement, explanatory power and predictive utility.

Mathematics is indeed abstract, often dealing with logical structures rather than empirical data, but psychology, especially in its modern form, does address empirical reality. Unlike mathematics, psychology relies heavily on empirical evidence to validate or falsify its hypotheses. Psychology uses behavioral proxies and neurobiological measures to ground mental processes in the physical world.