Science is based on presupposition. The goal is to test and revise the old presuppositions and to create new ones. Bateson reminds us of the following characteristics of science:

- Science never proves anything: Science sometimes improves hypotheses and sometimes disproves them. Yet, proof would be another matter. The truth about what can be perceived or arrived at by induction from perception is something else. We don’t know enough about how the present will lead into the future. We only use the rule of parsimony. Prediction can never be absolutely valid; so science can never prove some generalization or test a single descriptive statement and arrive at truth. Science is a way of perceiving and making what we may call “sense” of our percepts. Yet, perception only operates upon difference. All receipt of information is necessarily the receipt of news of difference and all perception of difference is limited by threshold.

- The map is not the territory and the name is not the thing named: There is a transformation between the report and the thing reported as naming is always classifying and mapping is essentially the same as naming.

- There is no objective experience: All experience is subjective as our brains make the images that we think we perceive. All perception has image characteristicsand to that extent, objects are our creation and our experience of them is subjective rather than objective.

Derived from these statements, Bateson asserts that the object of science should be looking for metapatterns- the patterns that connect patterns rather than aiming at objectivity or generalization. How is the world of logic that eschews circular argument related to a world in which circular trains of causation are the rule rather than exception? Logic is unable to deal with recursive circuits without generating paradox and that quantities are precisely not the stuff of complex communicating systems.