A new philosophical method was soon adopted by all the…

A new philosophical method was soon adopted by all the…

A new philosophical method was soon adopted by all the philosophers;

and it was by applying it to morals, politics and public economy that they became able in these sciences to follow a path almost as secure as that of the natural sciences, to admit only conclusions that could be proved, separating these from anything that might still be doubtful and uncertain, and to settle for not knowing anything that is and always will be unknowable.
Thus, the analysis of our feelings showed us that the development of our capacity for feeling pleasure and pain is the source of our moral ideas, the basis of the general truths which—being derived from those ideas—fix the unchanging necessary laws of right and wrong; and showed us the proper motives of obeying those laws, motives that are drawn from the very nature of our sensibility, i.e. from our moral constitution, so to speak. The same method became a kind of all-purpose instrument: they used it to improve the methods of the physical sciences, to clarify principles and to evaluate proofs of them; and they extended it to testing factual claims ·in history·, and to laws of taste. So this metaphysic, being brought to bear on every topic humans can think about, revealed for each branch of knowledge, the process of the human mind in it, the nature of the truths that form it into a system, and what kind of certainty can be achieved in it.

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