The first stage of critical thinking, acquiring knowledge, requires the ability to identify the core topic, key issues and main points of any discussion, news story or article -- also known as the five Ws (who, what, where, when and why). One might look for dates, events, locations or diagram components, people involved in an event or causes of an occurrence. This is the stage for discovering the basic information.
Comprehension, the second stage of critical thinking, involves uncovering implications, defining or interpreting the facts or drawing inferences on cause and effect to understand what was read or heard. This is the stage where a person draws connections between the new knowledge and what he already knows.
Critical thinking stage three applies the new information to current circumstances and toward problem resolution. Once a person knows and understands what has been heard, seen or read, that information can be used in real life. This is the stage where a person can direct information to any task that needs to be carried out.
Critical thinking stage four, analysis, includes pattern recognition, identifies meanings, perceives parts and wholes and acknowledges assumptions. Critical thinking means examining information to test the logic of the arguments and validity of the assumptions. This is the stage for dividing the information into building blocks, then classifying or organizing the blocks according to relationships with other pieces of information.
Synthesis, the fifth stage of critical thinking, makes "what if" statements, formulates predictions and makes deductions. Synthesis is the stage that allows a person to arrange and reorganize the newly analyzed information along with other bits of knowledge in creative ways to generate new ideas.
The sixth stage of critical thinking is evaluation, which assesses ideas, gauges value or worth, weighs options and gives advice about the new information, or which makes use of the new information or is based on the new information. Critical thinking first digests and fully analyzes all the information and its supporting evidence. Then a person moves into this stage, where she determines the credibility of the new knowledge and how to use it.