“It is important . . . that the habits of thinking in a free country should inspire caution in those entrusted with its administration, to confine themselves within their respective constitutional spheres, avoiding in the exercise of the powers of one department to encroach upon another. The spirit of encroachment tends to consolidate the powers of all the departments in one, and thus to create . . . a real despotism. A just estimate of that love of power, and proneness to abuse it, which predominates in the human heart, is sufficient to satisfy us of the truth of this Position.” -George Washington

Based on the selection, which constitutional principle is being discussed in the excerpt above? Use evidence from the text to support your answer.