I quote from Bertrand Russell’s “A fresh look at Empiricism”
The congress of Scientific Philosophy in Paris in September 1935, was a remarkable occasion, and, for lovers of rationality, a very encouraging one.
My first impression, on seeing the opening session, was one of surprise: surprise that there should be in the world so many men who think that opinions should be based on evidence.
My second impression, on hearing the papers and discussions, was one of further surprise, to find that the opinions advocated actually, conformed to this rule: I did not discover any of the signs of unfounded and merely passionate belief which, hitherto, has been as common among philosophers as among other men.
The instrument of mathematical logic, which Leibniz foresaw, has produced a large part, though not the whole, of what he had hoped from it: “Quo facto, quando orientur controversiae, non magis disputatione opus erit duos philosophos, quam inter duos computistas.
Sufficiet enim calamos in manus sumere sedereque ad abacos, et sibi mutuo (accito si placet amico) dicere: calculemus. [Having done so, when the issue is controversial, it will be necessary to dispute the two philosophers and two computists.
It will suffice to branch into his hands sedereque the bar and into another (calling a friend if you please) to Let us calculate. [Google]]
Better translation:
[If this is done, whenever controversies arise, there will be no more need for arguing among two philosophers than among two mathematicians.
For it will suffice to take the pens into the hand and sit down by the abacus saying to each other (and if they wish also to a friend called for help): Let us calculate.
[The Rise of Modern Logic]]
I was glad that Frege and Peano received due honors; for to them ultimately, the movement which gave rise to the Congress is mainly due.
At a previous conference in Paris, in 1900, at which I first made acquaintance both with Peano and with his work, I was struck by the fact that he avoided errors of syntax which, at this time, were almost universal, such as confounding 0 with the null-class, and the relation of membership with that of class inclusion.
The importance of syntax in philosophy has since been developed to its fullest extent by Wittgenstein, and by the Vienna school (it must be understood that ,Vienna‘ is a term of psychology, not geography), which contributed a number of interesting papers.
The Polish school of logicians, also, showed great vigour and originality.
(Russell 1936, S, 10f.)
I quibble a bit:
First Google’s latin is not very good yet and Leibniz should have written in German.
I share Russell’s enthusiasm for the rise of logic but I would characterize the new contributions as capturing the nature of logic, more than showing the utility of logic.
The developments that he applauds amount to digging out the hidden subconscious mechanisms that people, especially philosophers, use to come to conclusions.
These are the beautifully named “mere passionate beliefs”.
I agree that we still have a way to go to achieve Leibniz’s AI goals.