Buddha-mind (busshin 佛心) is the awakening (bodai 菩提, S. bodhi) that turns ordinary beings into buddhas. The Zen lineage is said to transmit Shakamuni's buddha-mind from master to disciple "without relying on scriptures" (furyū monji 不立文字). That wordless "mind to mind transmission" (ishin denshin 以心傳心) is likened to the kind of non-verbal communication that takes place when a carved seal (in 印), used in East Asia as a legally binding signature, is inked and pressed on a piece of paper. The awakened mind of the master presses directly, as it were, on the mind of the disciple, thereby replicating itself. A disciple whose understanding of the dharma is formally approved and documented by a master is also said to have received a "seal of approval" (inka 印可).