Did programme of predicate calculus algebraization succeed? In his essay An autobiography of polyadic algebras Halmos outlined why he is not satisfied with his baby. I suggest that Cylindric algebras are not genuine algebras either; what other algebraic structures have operators parametrized by something (cylindrification)? The situation is strikingly different from either boolean or relation algebra, each having a set of intuitive binary, unary, [and 0-ary] operations.
I suggest that the culprit is positional perspective onto relation attributes. Positional perspective is ubiquitous in math (sequences, function arguments, etc), so is easy to see why it penetrated into the world of relations. Positional perspective makes perfect sense for binary relations, this is why nobody challenged its adequacy for n-ary ones. However, it is easy to see that attribute positions are not essential to the ability to match values of the two different attributes of two different relations. Named attribute perspective is widely used in database theory and practice, which implies yet another algebraization of predicate logic.
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