ɪn wˈʌn θˈaʊzənd sˈɛvənhˈʌndɹɪd fˈoːɹɾi fˈaɪv, wˈɪt pˈʌblɪʃt ɐn ˌiːkwɪɹˈaɪ ˌɪntʊ ðə kˈɔːz wˌɪtʃ pɹəmˈoʊt ðə sˌɜːkjʊlˈeɪʃən ʌv flˈuːɪdz ɪnðə smˈɔːl vˈɛsəlz ʌv ˈænɪməlz wˌɛɹ hiː stˈeɪts ðætðə sˈoʊl, ˈɔːlsoʊ ɹᵻfˈɜːd tʊ æz ðə sˈɛnʃənt pɹˈɪnsɪpəl, ænd ðə bˈɑːdi hˈoʊld ˈiːkwəl ˈɪnfluːəns ˌoʊvɚ mˈuːvmənt ænd ðˈɛɹfoːɹ mˈeɪ ɡˈʌvɚn bˈoʊθ vˈɑːləntɚɹi ænd ɪnvˈɑːləntɚɹi ˈækʃən.
In 1745, Whytt published An Equiry Into the Cause Which Promote the Circulation of Fluids in the Small Vessels of Animals where he states that the soul, also referred to as the sentient principle, and the body hold equal influence over movement and therefore may govern both voluntary and involuntary action.