1. Philosophers emphasize determining truth through careful examination and justification rather than just belief. They subject their own knowledge and assumptions to doubt in order to learn. 2. For a statement to be considered true, it must be justified or proven through evidence, agreed upon as factual, and able to be applied and tested in the real world. 3. Philosophers distinguish truth from opinion by examining arguments closely for logical fallacies or biases that could undermine the reasoning. A variety of common fallacies and biases that weaken arguments are discussed.