The Summary of Physics Restored

106Those who establish the four Elements in as many humours acknowledge that moist nature can receive the four elemental qualities—indeed, is their subject. How, then, do they profess those qualities to be contraries when they place them in the same subject? Although the four humours are distinguished by their differences, they have a single basis common to all and the same root, namely moisture. Yellow bile, which represents fire, is no less a humour than phlegm, which they assign to Water; and let the same judgement apply to black bile and blood, even though they mingle the four Elements in moisture comparatively rather than absolutely.