Core beliefs are fundamental, deeply held beliefs that shape an individual's view of the world and themselves. These beliefs can be positive (e.g., "I am worthy of love and respect") or negative (e.g., "I am unlovable"), and they can influence how an individual thinks, feels, and behaves in various situations.

Core beliefs are often developed in childhood and may be influenced by experiences, family dynamics, as well as cultural and societal values. They can be difficult to change because they are so deeply ingrained and are often not consciously recognised.

Core beliefs can be categorised into several different types, below are few examples:

1. Self-worth: Beliefs about one's self-worth or self-esteem, such as "I am a good person" or "I am incompetent" or "I'm not good enough"

2. Personal control: Beliefs about one's ability to control and influence events in their life, such as "I am in control of my life" or "I am helpless."

3. Trust: Beliefs about the reliability and trustworthiness of others, such as "People are generally trustworthy" or "People are untrustworthy."

4. Love and relationships: Beliefs about love and interpersonal relationships, such as "I am worthy of love" or "I am unlovable."

5. Social norms: Beliefs about how one should behave in social situations, such as "I should always be polite" or "I should always be assertive.

Negative core beliefs are deeply held beliefs that are negative or distorted in nature and that shape an individual's view of the world and themselves in a negative way. These beliefs can be self-directed (e.g., "I am unlovable") or directed towards others (e.g., "People are untrustworthy").

Negative core beliefs can have a significant impact on an individual's mental health, influencing their thoughts, feelings, and behaviours in negative ways. For example, someone with the belief "I am unlovable" may have low self-esteem and difficulty forming and maintaining close relationships. Someone with the belief "People are untrustworthy" may have difficulty trusting others and may have difficulty forming and maintaining close relationships.

In Cognitive behavioural therapy (CBT), core beliefs are considered to be a key factor in the development and maintenance of mental health problems. Identifying and challenging negative core beliefs is an important part of the CBT treatment process.

This may involve helping the individual recognise the influence of their core beliefs on their thoughts, feelings, and behaviours, and developing more balanced or realistic alternatives.