Acharya Prashant explains that Bhishma's greed was his desire to be known as a worthy and dutiful son. He prioritized his father's sensual desires over the Truth, which eventually became the seed for the Mahabharata war. The speaker emphasizes that whenever one gives more importance to personal relationships or individuals over the Truth, the consequences are disastrous. Bhishma's vows were taken to satisfy his father's longing for Satyavati, a fisherman's daughter, rather than for any higher spiritual purpose. This highlights how even a scholar and politician like Bhishma can be blinded by misplaced loyalty and personal ego.