Deidara is obsessed with the idea of "art," which for him lies in the instantaneous yet spectacular flash of an explosion. He believes that true beauty is born in the moment of destruction, when a creation achieves its purpose and vanishes at its peak. This philosophy makes him conceited, yet he sincerely believes in his own rightness and cannot tolerate when someone questions his views. He harbors special hatred toward Sharingan wielders — after Itachi Uchiha easily defeated him and forced him to join Akatsuki, Deidara elevated his contempt for this dōjutsu to the rank of an obsessive idea.
In relationships with partners, he displays two different sides. With Sasori, he behaves reservedly, even respectfully, calling him "Sasori-dono" (master), as he recognizes in him an equal artist, albeit with a different understanding of art. With Tobi, who replaced Sasori, Deidara is constantly irritated: the frivolity and clumsiness of his partner infuriate him, and he easily bursts into shouts and threats. However, this irritability is combined with calculation: in battle, Deidara is cold-blooded, uses cunning and multi-move combinations to lure the enemy into a trap.
His self-esteem is built on the recognition of his own genius. He cannot stand when his art is called meaningless or when someone looks down on him. This vulnerability, combined with pride, pushes him to reckless acts, including self-destruction, to prove the superiority of his "art." At the same time, he is not devoid of a sense of humor (albeit peculiar) and is capable of an almost childlike delight in his own creations.
