The phrase "Melvva gaya gyan, bhuli gaya bhan" is often associated with the revered Jain Acharya Shri Hemchandra Acharya. He was a great scholar, poet, and philosopher in Jain tradition, and many such sayings are attributed to him. However, this exact saying reflects a traditional Jain teaching on humility and the pitfalls of ego after gaining knowledge. If you are searching for the specific person connected to this saying, it is commonly linked to Acharya Hemchandra.