“I believe in the principle of parsimony. The simplest explanation, the most eloquent explanation, is often the correct one,” Dr. Phil says, especially when it comes to your mental health. “If you’re thinking about what’s happening in your brain, in your mind, in your emotions, the simplest explanation is probably true.”

Dr. Phil says you first need to examine how you represent reality to yourself. “The way you’re talking to yourself makes you react the way that you react, so ask yourself, ‘What am I telling myself?’” he says. If you’re saying things to yourself that would be upsetting if you said them to another person, you need to challenge your thinking.

Learn more in the video above, including four questions to ask yourself to challenge what you say to yourself.

On Monday’s episode, Dr. Phil speaks to a 30-year-old man who insists he has schizophrenia – and his family who says that they have to constantly reassure him he’s not mentally ill, and it’s tearing them apart. Watch more here.