For example, the project of making machine intelligence is often criticized by showing ways that human intelligence does not involve symbolic computations, or by arguing that Turing computations cannot in principle give rise to human-like consciousness and mental states. These assumptions are discussed in Chapters One and Two. Although machine intelligence involves information processing, not all information processing is of the sort done by a Turing machine. Some aspects of intelligent behavior might require Turing computations, and other aspects not. Moreover, a computer might be intelligent in ways that are quite unlike human intelligence.
Human intelligence is only one example out of many possible kinds of intelligence.
Instead of using a Turing standard of human-like behavior for judging how intelligent a machine is, we could judge machine intelligence by how well the machine performs some task or range of tasks. For example, a machine that is able to do a good job at explaining, planning, using language, and perceiving, might be considered intelligent, even if it does not do these things in a human-like way. In Chapters Three and Four a methodology is given for building machine agents that do complex tasks requiring intelligence. In those chapters the tasks and strategies of intelligence are discussed. Once a task has been clearly defined in input-output terms, an agent can be built to perform it.