The mind of man can never be wholly barren. Through our whole lives we are subject to successive impressions; for, either new ideas are continually flowing in, or traces of the old ones are marked deeper. If, therefore, you be not acquiring good principles be assured that you are acquiring bad ones; if you be not forming virtuous habits you are, how insensibly soever to yourselves, forming vicious ones …

Joseph Priestley (1733-1804) British theologian, Dissenting clergyman, scientist, political theorist
Institutes of Natural and Revealed Religion, Vol. 1 “The Dedication” (Mar 1772) (1772-74)