Psychic equivalence is like when you and your friend are playing a game and you both agree on certain rules. Those rules become very important to the game, and if anyone breaks them, the game might not be fun anymore.
In the same way, when someone believes something is true, their mind treats it like it's true without questioning it. This is called "psychic equivalence" because their mind treats the belief and reality as the same thing.
For example, if someone believes that they're not good enough to make friends, their mind treats that belief as if it's true, even if it's not. They might feel sad, anxious, or scared of trying to make friends because their mind is stuck on the belief.
Psychic equivalence is important to understand because sometimes our beliefs can limit us and make us feel like we can't do things that we actually can do. If we learn to question our beliefs and find evidence to support whether they are true or not, we might be able to change our minds and be more open to new experiences.