 The production of general ideas from less general ones is, as we have seen, effected by the mind separating or deleting some components of the less general idea. The general idea of triangle could be produced by deleting equilaterality from the idea of an equilateral triangle. Similarly, ideas of greater complexity can be formed by combining less complex ideas. If, for example, one imagines a pink elephant, that idea is formed by combining an idea of an elephant with an idea of pink. The mental act of affirming or denying one idea of another is called judging. Mental operations of special importance to logic are those that result in propositions. This is the focus of the next part of the Logic.