A disclosure can be abstract.Logical formLearned from4 sentences. A conceptual model can be abstract.Logical formLearned from4 sentences. (Design ideas) can be abstract.Logical formLearned from4 sentences. A syntax may define an abstract (data structure).Logical formLearned from4 sentences. A preference can be abstract.Logical formLearned from4 sentences. An automata can be abstract.Logical formLearned from4 sentences. A learner can be abstract.Logical formLearned from4 sentences. A controversy can be abstract.Logical formLearned from4 sentences. Generalisations can be abstract.Logical formLearned from4 sentences. Pieces can be constituted-of-or-filled-with abstract art.Logical formLearned from4 sentences. A (symbol system) can be abstract.Logical formLearned from4 sentences. An abstract painting may fetch a price.Logical formLearned from4 sentences. Levels can be constituted-of-or-filled-with abstract thinking.Logical formLearned from4 sentences. (Art pieces) can be abstract.Logical formLearned from4 sentences. Approval can be abstract.Logical formLearned from4 sentences.