Syllogism is an iPhone app designed for introductory logic courses that allows users to construct syllogisms by choosing the quality and quantity of premises and conclusions, as well as the position of the middle term. This app also provides a feature to test the validity of syllogisms and display Venn diagrams.

With Syllogism, constructing syllogisms is made easy by selecting the quality and quantity of premises and conclusions. Users can also select the position of the middle term, which is crucial in constructing syllogisms. The app also includes a feature to test the validity of syllogisms, which is helpful in determining the correctness of the arguments.

Moreover, Syllogism provides Venn diagrams, which are useful for visualizing the logical relationships between different sets of data. This feature is great for those who are more visual learners and prefer to see the relationships presented in a diagram.

Overall, Syllogism is an excellent app for students taking introductory logic courses. It is easy to use, provides helpful features for constructing and testing syllogisms, and includes a visual aid for understanding the relationships between different sets of data.