If we pursue this matter further, we shall be told that the stable object is unchanging under the impact or stress of some particular external or internal variable or, perhaps, that it resists the passage of time.

The processes of perception are inaccessible; only the products are conscious and, of course, it is the products that are necessary.

Of all these examples, the simplest but the most profound is the fact that it takes at least two somethings to create a difference.

From the point of view of any agent who imposes a quantitative change, any change of pattern which may occur will be unpredictable or divergent.