Dhanush in and as Kara, directed by Vignesh Raja. (Courtesy: Vels Film International/X) Dhanush is not the kind of actor who gives motivational speeches easily. But at the pre-release event for his upcoming film Kara on Saturday , he said something with an unusual weight, because it was backed by a career that actually proves the point he was trying to make. At the event, Dhanush began his speech with a Tamil phrase rooted in ancient text. “Ennam Pol Vazhkai,” he said, explaining that it comes from the Bhagavad Gita and translates simply to: what you think, you become. He used it to walk the room through something personal. Around 2002, when he had just entered the film industry with his debut Thulluvadho Ilamai, directed by his father Kasthuri Raja, Dhanush said he had already told himself he would win a National Award. “All could have laughed,” he said, acknowledging how the claim would have sounded at the time as he was a newcomer. There was no visible path to that kind of recognition.…