the mind > mental capacity > memory > retention in the mind > memorization > memorize, learn by heart [verb (transitive)] > know by heart (2)
to can by heart: to know by heart. Also to can by rote. Obsolete.
transitive. To be able to recall (a text, one's part in a play, etc.) exactly; to have committed to memory. Originally to know by rote (see rote, n.1…