This introduction to discrete mathematics text combines theory with practicality. Discrete mathematics describes processes that consist of a sequence of individual steps, as compared to forms of mathematics that describe processes that change in a continuous manner. The major topics we cover in this course are single-membership sets, mathematical logic, induction, and proofs. We will also discuss counting theory, probability, recursion, graphs, trees, and finite-state machines.
Understanding the terms "single-membership" and "discrete" are important as you begin this course. "Single-Membership" refers to something that is grouped within only one set and systems that can be in only one state at a time, at the same hierarchical level. Similarly, "discrete" refers to that which is individually separate and distinct. Each of anything can be in only one set or one state at a time. This is a result of Aristotelian philosophy, which holds that there are only two values of membership, 0 or 1. An answer is either no or yes, false or true, 0% membership or 100% membership, entirely in a set or state, or entirely not. There are no shades of gray. This is much different from Fuzzy Logic (due to Lofti Zadeh), where something can be a member of any set or in any state to some degree or another. Degrees of membership are measured in percentage and those percentages add to 100%. But, even in Fuzzy Logic (multiple-membership, multiple-state, non-discrete logic), one ultimately comes to a crisp decision so that some specific action is taken, or not. For this course, it is enough to understand the difference between single-state and multi-state logic.
As you progress through the units of this course, you will develop the mathematical foundation necessary for more specialized subjects in computer science, including data structures, algorithms, cryptology, and compiler design. Upon completion of this course, you will have the mathematical know-how required for an in-depth study of the science and technology that is foundational to the computer age.
Thumbnail: graph. (CC BY-SA 4.0; Saint Louis University Department of Computer Science)