Howard Gardner, an American psychologist, proposed the Theory of Multiple Intelligences. In his book Frames of Mind, he pointed out that he did not believe there was "one form of cognition which cuts across all human thinking." There are multiple intelligences with autonomous intelligence capacities. " So, intelligence cannot be viewed as a single entity.Gardner initially proposed eight types of intelligence, which later on he increased to nine. Thus, Gardner views each individual as a unique combination of various intelligences; hence, we cannot say that one is more intelligent and another is less intelligent.According to Howard Gardener's theory of multiple intelligence, intrapersonal intelligence refers to the ability to discriminate complex inner feelings and to use them to guide one's own behavior, as "intrapersonal intelligence" refers to thecapacity to understand one's own feelings, fears, and desires. ability to understand oneself, including motivation and emotions.One has the potential to plan, regulate, and manage one's own life effectively.Hence, it could be concluded that, according to Howard Gardener's theory of multiple intelligence, intrapersonal intelligence refers to the ability to discriminate complex inner feelings and to use them to guide one's own behavior.Additional Information The nine types of intelligence, as given by Gardner, are:Linguistic intelligence refers to the ability to use language. It is the capacity to use spoken and written words in a skilled way.Logical-mathematical intelligence is the ability to use logical reasoning and mathematical ability. Individuals high on this intelligence have good abstract reasoning, critical thinking, and are good at dealing with numbers.Musical intelligence is the ability to use rhythms, sounds, and patterns to create, compose, and perform music. It involves sensitivity to music and the ability to recognise and manipulate musical patterns. Bodily-kinesthetic intelligence is the ability to use and control ones body movements and actions. Dancers and sportspeople are usually high in such intelligence. Spatial intelligence is the capacity to perceive, understand, and use spatial and visual information effectively. Such people are good at spatial orientation and forming visual images and patterns.Interpersonal intelligence refers to the ability to understand others and social interactions. They can understand the emotions and perspectives of others and relate well to others.Intrapersonal intelligence is the ability to understand oneself and know ones thoughts, emotions, feelings, motives, and desires and how these influence one's behavior.Naturalistic intelligence is the ability to recognise and understand the various patterns in nature. It includes sensitivity to nature with all its features, including flora, fauna, and all biodiversity.Existential Intelligence: Gardner added existential intelligence as the ninth intelligence, which refers to the sensitivity and capacity to tackle deep questions beyond sensory data and about human existence. It concerns the "big picture" in life and the ultimate truth of life. Cosmologists and philosophers are high on this aspect of intelligence.