Tutorial 2 Example: How Experts Symbolize
[This is a film-- press the 'play' symbol.]
Some different logical systems use different logical symbols one from another. For example, the symbols '∧', '&' and '.' are all commonly used for the English 'and'. The explanatory and illustrative film uses one of these logical symbols, '∧', in fact. It may be that the logical system that you are familiar with, and are using, is different. But this small and insignificant detail does not affect the central explanatory purpose of the film. Some of the other films may also have similar mild inaccuracies in peripheral detail (depending on what you are used to).