I read about cases of non-literal infringement all of the time. Seldom, if ever, is the infringing work identical to the original. To prove an infringement claim, the plaintiff must establish (1) access to the original work by the accused infringer and (2) substantial similarity between the original and allegedly infringing work.
There is little doubt that Joseph Smith had access to View of the Hebrews. The book was published 7 years before the Book of Mormon. Ethan Smith lived in Poultney, Vermont, the same town as Oliver Cowdery. In fact, Ethan Smith was the pastor of the church that Cowdery's family attended from 1821 to 1826. There is also some evidence that Cowdery had a copy of View of the Hebrews. Given the close relationship between Cowdery and Joseph Smith, it is highly likely that Joseph had access to the book.
The requirement for substantial similarity is also likely satisfied. As outlined by Grant Palmer, the parallels include:
- -extensive quotation from the prophecies of Isaiah in the Old Testament
-the Israelite origin of the American Indian
-the future gathering of Israel and restoration of the Ten Lost Tribes
-the peopling of the New World from the Old via a long journey northward which encountered "seas" of "many waters"
-a religious motive for the migration
-the division of the migrants into civilized and uncivilized groups with long wars between them and the eventual destruction of the civilized by the uncivilized
-the assumption that all native peoples were descended from Israelites and their languages from Hebrew
-the burial of a "lost book" with "yellow leaves"
-the description of extensive military fortifications with military observatories or "watch towers" overlooking them
-a change from monarchy to republican forms of government
-the preaching of the gospel in ancient America
Whether this would be enough from a legal perspective is debatable. However, the sheer number of parallels, along with the copying of words and phrases, such as "many waters," is good evidence that Joseph Smith used concepts from the View of the Hebrews in the Book of Mormon. Successful copyright infringement claims against authors and Hollywood movie producers have been made with less evidence.
Gardner is correct, however, that one must be careful about confirmation bias. Selecting only the parallels can make any two documents appear to be related. On the other hand, where there is the use of exactly the same language (e.g., crossing "many waters"), where a variety of words could have been used, the case for infringement is increased. Likewise, where unusual or novel concepts exist in both works, such as two groups of people (one civilized, the other uncivilized) engaging in warfare to the extinction of the civilized group or a change in forms of government in ancient America from a monarchy to a democracy), the probability that such concepts were independently developed by both authors is extremely low.