Start with the obvious.
>>422597
Hume, Russell, Popper, Kuhn, Lakatos, Feyerabend.
>>422597
Richard Feynman was pretty based.
Leibniz
>>422597
>>422597
Descartes
>>422597
Linnaeus was a wanker tbqh
As far as interesting characters go, Isaac Newton is up there. We might see the Principia as a rational work of science, but he was also a mystic and an alchemist. John Maynard Keynes was fascinated by Newton and wrote about him with deftness and sincerity:
>Newton was not the first of the age of reason. He was the last of the magicians...
>>422964
>>Newton was not the first of the age of reason. He was the last of the magicians...
Why not both?
>>422965
^That.
There's no tangible reason that exploration and experimentation of the natural world should be mutually exclusive to exploration and experimentation of spiritual matters.
RE: OP, I'm fond of Haeckel.
>>422965
Because he wasn't a contradictory character as we might view his spiritual explorations alongside his scientific ones today; there wasn't a sense of dichotomy with the mundane and the mystical which is I think what Keynes expresses beautifully.