Process and Reality

"Coherence," coherenceIn Whitehead's system, coherence means that no fundamental idea can be fully understood or exist in isolation from the others. as used here, means that the fundamental ideas used to develop the system rely on one another so that, if they are taken in isolation, they become meaningless. This requirement does not mean that the ideas are simply defined by each other; rather, it means that the essential, indefinable core of any one concept cannot be separated from its relationship to the other concepts. The ideal of speculative philosophy is that its basic notions should not seem capable of being detached from one another. In other words, it is assumed that no entity can be understood in complete isolation from the system of the universe, and it is the task of speculative philosophy to demonstrate this truth. This interconnectedness is what constitutes its coherence.

The term "logical" logicalWhitehead uses this to mean the standard rules of consistency and inference that govern sound reasoning. carries its ordinary meaning. This includes "logical" consistency (an absence of contradictions), the definition of complex ideas in logical terms, the way general logical concepts are shown in specific examples, and the principles of reasoning. It should be noted that these logical concepts must themselves find a place within the overall philosophical system.

It will also be noticed that this ideal of speculative philosophy has a rational side and an empirical side. The rational side is expressed by the terms "coherent" and "logical." The empirical side—the part based on observation—is expressed by the terms "applicable" and "adequate." However, these two sides are joined together by clearing up a confusion in the previous explanation of the word "adequate." adequateA system is "adequate" if it can account for all types of experience, not just a selected few. The adequacy of a system over every item does not just mean it works for the items we have happened to consider so far. It means that the "texture" of the experience we observe is such that all related experience must share that same texture. Thus, a philosophical system should be "necessary," in the sense that it carries within itself its own proof of being universal across all experience—provided that we limit ourselves to things that connect with immediate facts. But what does not so communicate is