Abraham Maslow is widely recognized as one of the founders and leading proponents of humanistic psychology.

Humanistic psychology emphasizes the inherent goodness and potential of individuals, as well as their capacity for personal growth and self-actualization.

Abraham Maslow's hierarchy of needs is a motivational theory that proposes that individuals must satisfy certain basic needs before they can progress to higher-level needs, such as self-actualization.

Self-actualization is a key concept in humanistic psychology, referring to the process of realizing one's full potential and becoming the best version of oneself.

Carl Rogers believed that empathy and unconditional positive regard are essential qualities for effective therapy, as they create a safe and supportive environment for clients to explore their inner experiences.

Phenomenology is a philosophical approach that emphasizes the importance of understanding the subjective experiences of individuals, which is a central tenet of humanistic psychology.

Viktor Frankl, a prominent existentialist psychologist, introduced the concept of existential anxiety, which refers to the anxiety that arises from the awareness of one's own mortality and the meaninglessness of existence.

Solipsism is a philosophical concept that posits that the only reality is one's own subjective experiences, which can be a challenge in humanistic psychology's emphasis on understanding others' perspectives.

Viktor Frankl, a prominent existentialist psychologist, believed that finding meaning and purpose in life is essential for psychological well-being.

Self-awareness is a key concept in humanistic psychology, referring to the process of becoming conscious of one's own thoughts, feelings, and behaviors.

Rollo May, a prominent existentialist psychologist, emphasized the importance of authenticity and being true to oneself, arguing that inauthenticity leads to anxiety and depression.

Nihilism is a philosophical concept that posits that life is meaningless and that there is no inherent purpose or value in existence, which can be a challenge in humanistic psychology's emphasis on finding meaning and purpose.

Rollo May, a prominent existentialist psychologist, emphasized the importance of choice and freedom in human existence, arguing that individuals have the power to shape their own lives and create meaning.

Individuation is a concept in humanistic psychology that refers to the process of integrating one's conscious and unconscious experiences, leading to a more complete and authentic sense of self.

Carl Rogers believed that creating a safe and supportive environment for clients in therapy is essential for facilitating personal growth and change.