Deductive logic
Reasoning from the general to the specific. In this approach, you begin by specifying a theory. From the theory, you generate hypotheses about what should happen in specific circumstances. If you wish to test the theory, you can collect data to see whether what you hypothesize happens. If it does, the specific data you examine provide support for your theory. The direction of reasoning is often thought of as “top down,” from theory (the general) to data (the specific).
Inductive logic
Reasoning from the specific to the general.
In this approach, you begin by examining concrete events or
phenomena—your data. From the data, you attempt to identify larger
categories of phenomena (or constructs, or variables), and to
understand the relationships among them. In other words, you use the
data to build theory. The direction of reasoning is often thought of as
“bottom up,” from the data (the specific) to theory (the general).