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  • Philosophy of Science Assignment 060519

    History of Science & Scholarship

    Philosophy of Science Assignment 060519

    1、T→O，O，所以T。自己用真值表验证。 This inference is obviously wrong. “T→O is true” if and only if “it is not the case that T is true and O is false.” When O is true, then no matter what T is, T→O is always true, so O being true is of no help in judging whether T is true or false. On the contrary, the inference “T→O, ¬O, therefore ¬T” is correct. However, the analogy “T→O, O, therefore T” is not suitable for describing actual scientific explanation. Actual scientific explanation is usually still fairly rigorous—though not “absolutely correct,” at least in general it is more worthy of belief than this obviously mistaken logical inference. In…

    sciencephilosophy of sciencelogiccausality
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  • I read a crank-science paper… @_@

    History of Science & Scholarship

    I read a crank-science paper… @_@

    Today I finally, astonishingly, read through an entire paper by a “popular-science crank”: http://hk.netsh.com/eden/bbs/6214/html/tree_7386694.html Alas, every paper by a popular-science crank is a classic. They have quite distinctive features: their first-order research is a mess, but their second-order research is actually quite meaningful. Since reading 《Four-Dimensional Mechanics》 back in high school, this is once again the chance encounter that has led me to a complete popular-science-crank article; revisiting it a bit is fine too, fortunately I still remember what a popular-science crank is all about…… First let me quote a few funny lines: This paper is the product of the author’s many years of thought, and has recently been thoroughly…

    book readingnotesScientific RevolutionLiu Huajie
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  • Does Life Have Meaning or Not?

    Philosophy & Thought

    Does Life Have Meaning or Not?

    I am an optimist. I love this world, filled as it is with beauty and ugliness; for me, life is of course meaningful, and meaningful in a sacred sense. Yet this belief that “life has meaning” is, for me, a “postulate”: it is unreasonable! And it is much like Euclid’s fifth postulate, or, more precisely, like the “law of excluded middle” in logic—“P or not P” is always true; how can there still be room for debate? Yet intuitionistic logic and certain many-valued logical systems do not accept this, and they can nevertheless construct a logically self-consistent system of their own. It is hard to determine, by argument within logic…

    philosophylogicdeathnihilism
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