Logic programming that computational steps cannot be logically deduced. However, in concurrent logic programming, any result of a terminating computation is a logical consequence of the program, and any partial result of a partial computation is a logical consequence of the program and the residual goal (process network). Consequently, the indeterminacy of computations implies that not all logical consequences of the program can be deduced. Concurrent constraint logic programming combines concurrent logic programming and constraint logic programming, using constraints to control concurrency. A clause can contain a guard, which is a set of constraints that may block the applicability of the clause.
Language, Truth, and Logic be true or false. Ethical or aesthetic judgments express feelings, not propositions, and have no objective validity. Value-judgments are not analytic, and are not verifiable as 'matters of fact.' According to Ayer when we argue about whether a value-judgment is right or wrong, we are really arguing about the empirical facts on which a value-judgment is based, or about the logical interpretation of empirical facts. We cannot argue about something that cannot be expressed as a proposition. We can only argue about something that can be analytically or empirically verified. For Ayer, metaphysical statements, such as statements about transcendent reality,