There is a tradition in the world that new beliefs correspond with new ideas. Indeed, since the Renaissance there has been much contention for this often unnamed territory, of the central nature of ideas. At the time of Plato, 'idea' itself was a new idea, which struggled to make generic what was already known as history, story, feeling, or anger.
Plato's ideas were sometimes mistaken to mean that ideas were 'one thing', and that all thinkers were part of one collective 'idea'. There is some suggestion that the concept of 'collective' and 'being everything' are still echoing even today. Perhaps it is because these concepts happen to be as useful to us as they were to the ancient Greeks.
Many concepts, like value, truth, and political power, became swept up in a kind of pick-up culture, in which gradually intellectuals attempted to realize every possible combination. This occurred by generalization and specialization, and also the re-application of popular or difficult concepts. Much of this occurred without fully conceptualizing just what this secondary, central process 'was'.
During the Age of Reason, Greek concepts were re-introduced, and after the Copernican Revolution, people struggled to put humanity at the center of the picture. The solution to this puzzle became the epigram that man was a thinking animal, and Descartes' expression 'I think therefore I am'---cognito ergo sum. Because the center of the puzzle was also the most direct experience, humanity became forever a subject of 'reasons'.
Every new principle seemed to introduce a new stigma, a new divide, a new hypothesis, a new science.
Here are some of the principles that arose and contradicted one another:
1. Ethics, Ownership
2. Mathematics, Psychology
3. Creativity, Certainty
4. Determinism, Ambiguation
5. Arbitration (Law), Confusion
6. Intelligence, Madness
7. Prosperity, Nature
8. Origin, Infinity
9. Tradition, Action
Because many of the epistemological concerns were left unresolved, the theories became increasingly complex.
Many combinations were tried. Such as creative intelligence, natural ownership, mathematical infinity, and traditional psychology.
The theory of personal meaning seemed to depend on whatever solution worked, and the specific method adopted did not always seem to have to fit a definition of validity.
Nonetheless, occasionally the methods of reasoning seemed to hit a bottleneck.
For example, Kant's theory in the Metaphysics of Morals produced a contradiction between the learned and the unschooled, and even between theologians. His new theory had the symptoms of subjectivity, what became later known as moral relativism: the world without a known God.
For philosophers, this raised an interesting muddle of fascinating problems. For example, Berkeley proposed that the world fundamentally consisted entirely of ideas, defined by human psychology. Later, theorists ordained that we wouldn't know the difference if we were, in reality, brains stimulated in a vat.
In some ways this was the beginning of real epistemology, and in some ways perhaps it was the end. More often than before, mental theories were 'un-moored' from any notion of certainty, while frustratingly, simultaneously, a defensible viewpoint increasingly depended on the subject of definitions.
A certain ativism produced in the work of linguists, metaphysicians, and even, it became realized, mathematicians and scientists, led to new inquiries in which validity was more nepotistical, and in which personal significance was seen as standing on higher ground than a mere 'critic' or 'interlocutor'. One of the developments of this was that information, formerly assumed to be something such as 'the set of all arbitrary numbers' or 'the shoes that George wears', was now itself potentially elevated. For information that could be 'merely statistical' could also have a special 'linguistic value' or connotation.
This was expressed in works such as the following:
On Sense and Reference, Frege
A Room of Her Own, Plath
Wei-Wei Isms, by Weiwei Ai
Siteless: 1001 Building Forms, by Blanciak
The overall move was towards an epistemology that was more inclusive, and not prone to the old errors of selective inclusion, rhetorical exclusion, and perhaps oppositeness and mere novelty.