This is because their concept of consciousness was different to the western. In Buddhism there are six forms of consciousness according with each of the senses (including mind).
“Feeling, perception, & consciousness are conjoined, friend, not disjoined. It is not possible, having separated them one from another, to delineate the difference among them. For what one feels, that one perceives. What one perceives, that one cognizes. Therefore these qualities are conjoined, not disjoined, and it is not possible, having separated them one from another, to delineate the difference among them.”—Majhima Nikaya 43
The Buddhist view is helpful because an unwholesome mind state for example, can be identified as a consciousness complete with feeling and perception. Mental formations are then able to challenge that consciousness, preferably by understanding its origin, and investigating the wrong perception which caused it to arise, or blocking it by one of the tactics in Majhima Nikaya 20.
If you have a friendly heart, this is ‘citta’. It is not ‘friendly consciousness’ or ‘friendly intellect’. If you have intelligent mind, it is intelligent intellect (mano) rather than ‘intelligent heart’ (‘citta’). If you have clear discerning consciousness, it is not ‘discerning heart’ (‘citta’).