score:13
How do believers in post-mortal consciousness respond to this article?
First, by comparing it to this article from JewishEncyclopedia, which disagrees. We'll call the article cited in the OP "article A", and the article in my link "article B". Article B is clear that there is communion among the dead.
Second, by pointing out several of the presuppositions upon which Article A's case rests:
Article A essentially assumes all Old Testament evidence dis-favorable to its preferred conclusion is forgery/pseudepigraphy. The article's position crumbles quickly if these premises are discarded.
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Is it true that post-mortal consciousness is nowhere expressly taught in Holy Scripture?
When Kohler says "Holy Scripture" he means what ancient Jews called the Tanakh, and what Christians call the Old Testament.
I dispute the claim that post-mortal consciousness is absent from the Old Testament (e.g. Isaiah 9:2, Isaiah 14:9-11, Isaiah 24:22), but I do acknowledge that the concept is more clearly taught in the New Testament (e.g. Luke 16, 1 Peter 3 & 4) than in the Old.
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Is it true that the belief in post-mortal consciousness came to the Jews from contact with Greek thought and chiefly through the philosophy of Plato?
This is a third cause fallacy. That both Greek & Jewish writers expressed opinions in favor of post-mortal consciousness does not mean the Jews got the idea from the Greeks any more than it means the Greeks got the idea from the Jews, or that they both got it from another, earlier source.