An Analogical Approach
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In an atomistic, analogical approach to description, our task is to select specific occurrences to model behavior after. In this kind of approach we always predict behavior in terms of positive contexts. Given a positive context x = a l a 2...a k (where the a i are each primitive unanalyzable elements), we first determine all the positive supracontexts of x; that is, all the positive contexts that contain x as a subcontext. For instance, if x = abc, then the positive supracontexts of x, in addition to abc itself, are ab—, a—c, —bc, a—, —b—, ——c, and ---. In order to list the positive supracontexts of any given positive context x, we systematically remove the primitive elements from x. In general, if x contains k primitive elements, then there will be 2 k positive supracontexts for x. With no primitive elements removed we have the given primitive context x = a l a 2...a k . Removing one primitive element, we have k possible supracontexts:
$$- {{a}_{2}} \cdots {{a}_{k}}{{a}_{1}} - {{a}_{3}} \cdots {{a}_{k}} \ldots {{a}_{1}}{{a}_{2}} \cdots {{a}_{{k - 1}}} -$$
The next step is to remove two primitive elements, which will give us k(k—1)/2 supracontexts:
$$- - {{a}_{3}} \cdots {{a}_{k}} - {{a}_{2}} - {{a}_{4}} \cdots {{a}_{k}} \ldots {{a}_{1}}{{a}_{2}} \cdots {{a}_{{k - 2}}} - -$$
Continuing in this fashion, we keep eliminating more primitive elements. Eventually we arrive at a stage when only one primitive element remains in each supracontext. At this stage there will be k supracontexts:
$${{a}_{1}} - \cdots - - {{a}_{2}} - \cdots - \ldots - - \cdots - {{a}_{k}}$$
Finally, we get the null supracontext υ, for which all the k primitive elements have been removed: ——... —.