Dear Steve,
You asked: "who was the best rationalist, the most rational and logic between these persons,
Dedekind, Cantor,Riemann,Gauss,Poincarré,Pierce,Euler,Stern,Dirichlet,Hilbert
."
Among my favorites are Euclid, Galilei, Euler, and many others also including Peirce. The latter stands for what the other you mentioned made or considered outdated.
When I wrote pre-Dedekind mathematics, this was a questionable simplification. While I found the old and physically correct Euclidean notion of number still maintained up to the time of Dedekind, its mathematical mutilation to just a single point begun earlier. Let me consider the row Gauss, Riemann, Stern, Dirichlet, Dedekind, Cantor, Poincaré, Hilbert.
The book by Nahin to which Edwin Klingman pointed me made me aware of even elder roots. My admiration for Gauss has become overshadowed when I got aware of his arrogance. More factually, I dislike that he promoted the complex plane, which goes back to Wallis, Wesse, Argand, and Hamilton, without to stress that it is not accessible via Euler's identity but via an omission.
I see Riemann, Cauchy and others preferring to create pure mathematics that neglects the link with its application in physics. What about Moritz Stern, I did not find him mentioned in literature that describes the origin of set theory. While Dirichlet was lacking a solid education, he was nonetheless very influential in particular on Dedekind. Dedekind on his part managed to cautiously and elegantly advertise what I consider a clever seemingly rigorous self-deception. Frankly admitted having no evidence he kindly asked to nonetheless believe him. While G. Cantor had the same intention, he managed to provide stunning evidences and get a nimbus of a genius. Poincaré is told having called Cantor a charlatan. Maybe, he was not quite wrong in that. I like Hilbert's transformation. Hilbert was very disappointed when his successor Hermann Weyl rejected large parts of set theory. In all I see Hilbert's influence on physics with very mixed feelings. It was Hilbert who denied for mathematical reason that past and future are fundamentally different from each other.
Regards,
Eckard