The greatest part, I should say above two-thirds of the medicinal virtues, consist in the quintessence or occult property of simples, of which we can have no other instruction than use and custom; for quintessence is no other than a quality of which we cannot by our reason find out the cause.
Zatirik gehiena, eta, uste dut, bertute sendagarrietarik bi herenak baino gehiago, sinpleen kintaesentzian edo nolakotasun gordean dautza, hartaz erabilpenik beste irakaspenik ez baitezakegu ukan: zeren kintaesentzia geure arrazoiaren bidez haren kausa aurkitzen ez dakigun nolakotasun batez besterik ez da.