<P> Erasistratus ( / ˌɛrəˈsɪstrətəs / ; Greek : Ἐρασίστρατος ; c. 304 -- c. 250 BC ) was a Greek anatomist and royal physician under Seleucus I Nicator of Syria . Along with fellow physician Herophilus , he founded a school of anatomy in Alexandria , where they carried out anatomical research . He is credited for his description of the valves of the heart , and he also concluded that the heart was not the center of sensations , but instead it functioned as a pump . Erasistratus was among the first to distinguish between veins and arteries . He believed that the arteries were full of air and that they carried the `` animal spirit '' ( pneuma ) . He considered atoms to be the essential body element , and he believed they were vitalized by the pneuma that circulated through the nerves . He also thought that the nerves moved a nervous spirit from the brain . He then differentiated between the function of the sensory and motor nerves , and linked them to the brain . He is credited with one of the first in - depth descriptions of the cerebrum and cerebellum . </P>
<P> Erasistratus ( / ˌɛrəˈsɪstrətəs / ; Greek : Ἐρασίστρατος ; c. 304 -- c. 250 BC ) was a Greek anatomist and royal physician under Seleucus I Nicator of Syria . Along with fellow physician Herophilus , he founded a school of anatomy in Alexandria , where they carried out anatomical research . He is credited for his description of the valves of the heart , and he also concluded that the heart was not the center of sensations , but instead it functioned as a pump . Erasistratus was among the first to distinguish between veins and arteries . He believed that the arteries were full of air and that they carried the `` animal spirit '' ( pneuma ) . He considered atoms to be the essential body element , and he believed they were vitalized by the pneuma that circulated through the nerves . He also thought that the nerves moved a nervous spirit from the brain . He then differentiated between the function of the sensory and motor nerves , and linked them to the brain . He is credited with one of the first in - depth descriptions of the cerebrum and cerebellum . </P>
who was the greek physician who distinguished the veins from the arteries
who was the greek physician who distinguished the veins from the arteries
Erasistratus
Erasistratus