There are many definitions of critical thinking out there. Some are short, sweet and simple, while there are others that are extremely long and try to include every single aspect of critical thinking. I prefer to go with the short one: "Critical thinking is the process of making clear and reasoned judgements' by Beyer.
There are three key elements in this
1. Clear thinking and communication : Our thinking and communication needs to be clear. You may ask what can go wrong with it? Well, the most common causes of leading one away from critical thinking are :
(a) ambiguity arising from semantic ambiguity or syntactic ambiguity. Consider these sentences : "This fisherman does not use glasses". Glasses could either mean spectacles, or they could mean drinking glasses. Now consider another sentence " She saw the fisherman with binoculars" . In this sentence the ambiguity arises due to the way the sentence is constructed. We don't know whether 'she used the binocluars to see the farmer, or whether the farmer she saw a farmer having binoculars with him. This is called Syntactic ambiguity
(b). Usage of relative words such as : good, better, least, most, large, small etc. Unless you and the audience have a common understanding of what these words mean, and agree on how the measurement is to be done, each of these words will bring out different measures in your mind.
(c) Usage of vague terms or words: In this context when I say vague, what I mean is that the same word can be interpreted by different people in different ways. For example, if we were asked who was the greatest President of India since Independence, each of us is likely name a different person. And if asked why, each of us will have different reasons. Obviously what 'greatest' means to each of us is different. It is important to avoid the usage of vague terms or if we must use them, then we should define what those terms mean in the given context.
2. Process : The presence of this word clearly indicates that critical thinking involves some steps before we can arrive at a conclusion. When we are trying to solve a problem or make a plan or strategy, the process I recommend is to take a 360 degree of the issue before finalizing any solution. To achieve this comprehensive view I say that we should always start with the evidence, analyze it, develop several alternative solutions and narrow down to one. For any finalized plan or solution, we should explicitly articulate the assumptions made that are necessary for the solution to work. Implications of each solution should be thought through and again explicitly articulated. Finally I recommend that we look at the solution from the point of view of other stake holders. For example, a price discount on the product will elicit different reactions from the Sales Manager, the Marketing Head, The Finance head and finally the CEO of the organization. While the Sales Manager may welcome it because it will increase overall sales volume and make it more competitive and easier to sell, the Marketing Head may have apprehensions about the price discount diluting the brand image. The CEO and Finance heads would be concerned about lowered profitability. Going through the entire process ensures that we have looked at the problem from all possible angles before finalizing a solution
3. Reasoned judgements: We look at evidence, situations and facts and draw conclusions based on what we see, hear or know. In the process of arriving at these conclusions we are expected to be logical. Logic is the study of evaluating various types of reasoning and developing good reasoning. Since we are not formally trained in informal logic, we end up making several errors in our reasoning. Moreover rhetoric, fallacies and cognitive biases can lead to judgements which are not purely based on logic.
If we want to be good critical thinkers, we do need to learn about logical reasoning and develop an understanding of all the different ways of how poor communications, rhetoric, fallacies and cognitive biases can sabotage good reasoning.