Letters 108.18

Sextius believed that man had enough sustenance without resorting to blood, and that a habit of cruelty is formed whenever butchery is practised for pleasure. Moreover, he thought we should curtail the sources of our luxury; he argued that a varied diet was contrary to the laws of health, and was unsuited to our constitutions.

Seneca, Letters to Lucilius 108.18, translated by Richard Mott Gummere