According to Buddhist teachings, the attachment to the five aggregates (form, feeling, perception, mental formations, and consciousness) and the identification with the six senses (sight, hearing, smell, taste, touch, and mind/manas) is considered a fundamental cause of suffering.
The Buddha emphasized the impermanent and conditioned nature of these aggregates and senses. He taught that clinging to them as a sense of self or as a source of lasting happiness leads to attachment, craving, and ultimately suffering. The worldly, or puthujjana, who are unaware of the peril of these aggregates and senses, tend to identify with them and mistakenly believe them to be who they are.
Instead of clinging to the notion of a self within the aggregates, etc., the Buddha taught that the true essence, known as the Tathagatagarbha or Buddha Nature, resides within all beings. As stated in the Mahaparinirvana-sutra,
"The ātman is the Tathagatagarbha. All beings possess a Buddha Nature: this is what the ātman is. This ātman, from the start, is always covered by innumerable passions (klesha): this is why beings are unable to see it."
However, due to the influence of numerous afflictions, this inherent Buddha Nature remains obscured and difficult to perceive. By understanding this concept, one can embark on a path of uncovering and realizing their true nature, thereby transcending the limitations imposed by attachment to the aggregates and senses.