Treating a patient involves a literal subject, a unique individual. Is medicine then, not science? It's actually arguably the oldest science, from before alchemy became chemistry, and natural philosophy became physics.
What you are doing is what I'd call 'physics chauvenism', the implicit assumption that things are science in so far as and to the extent they are like physics. That is a mistake. Processes and practices vary massively between fields, like for example whether replicability is possible - science can still study freak or one-off events.
As well as sociology, social sciences are considered to include: anthropology, archaeology, economics, human geography, linguistics, management science, communication science and political science. Archeology is a good example, there's always a lot of questions that can't be answered, informed guesswork, and subjective input, but there's also rigorous carbon dating, complex methods to preserve dig data, and materials and language analysis. A 'soft' subject can still be approached in a scientific way, that uses scepticism, tries to counter expectation biases, uses tests to distinguish between hypothesees and so on.
I don't know why you insist on saying 'societal science' instead of sociology.
any subject could choose to "think differently from the proposed
societal base paradigm"
Any gas molecule can behave in a way that violates the ideal gas laws. But guess what happens when you have lots of molecules. Pretty good predictions.
Thus it's impossible to formulate "societal paradigms"
I don't think you understand what a paradigm is. In science we had: medicine as balancing the humours when viaducts were the height of technology allowing far bigger cities to exist (by reducing risk of cholera), a clockwork-universe picture when clockwork was peak technology, a steam-engine picture of the unucerse with thermodynamics, and now we see brains as computers and expect quantum gravity to come from thinking about information flow. Our paradigms are like mental furniture, the things we understand the world with, and use to talk about it.
It's not that no one could think in different ways, they did, that's how the paradigm changed. But paradigms aren't just like blinkers, they are also like lenses that help us focus on types of object and dynamic. Was capitalism a sudden total break from feudalism? No, of course not. But land ownership stopped being the only and defining form of wealth, with new ways to fund trade voyages and industrialisation.
I think this quote defines how a paradigm shifts:
"You never change things by fighting the existing reality. To change
something, build a new model that makes the existing model obsolete."
Anyone can think in a unique weird way. Only a visionary, can see the world as those in the future will come to take for granted. But, regardless, the wheel will turn. Sociology can help us go beyond just history, into how people saw the world and understood themelves, and how that affected their actions. And by doing so we can better catch ourselves in a similar process, doing things future people will look back on incredulously.