Systematic rationality often works. This is unquestionably true, and important. However, the analysis in Part One suggests that rationality doesn’t work the way rationalism mistakenly supposed. It must work some other way. How?
The answer—explained in Part Three—depends on an understanding of how everyday effective thought and action (“reasonableness”) work in practice. So Part Two looks at that, as a prerequisite to Part Three’s rethinking of rationality.
Reasonableness works directly with reality, whereas rationality works with formalisms. Rationalism assumes that a formalism somehow reflects reality, and glosses over questions about how that works. In fact, in technical work, the connection is often extremely complex, but is usually ignored in theoretical explanations of how science and engineering work. (It is not ignored in practice, but this aspect of practice is overlooked in rationalist explanations.) Part Three is about how rationality depends on reasonableness to connect with reality; first we need to understand how reasonableness works on its own.
Understanding reasonableness is also a prerequisite to understanding meta-rationality. They are not the same; in Part Four, I will develop a three-way contrast between reasonableness, rationality, and meta-rationality. (Sneak preview: meta-rationality is “reflective”—it stands outside all systems—and coordinates multiple reasonable and/or rational points of view; reasonableness does not. What’s distinctive about meta-rationality is its appropriation and altered re-use, or distinctive deployment, of rational methods, within a different overarching understanding of broader scope.)
Cross the river when you come to it
The rationalist framework overlooks contextual resources, which makes rationality artificially difficult.
Each of the problems faced by rationalism boils down to nebulosity giving rise to unenumerable potentially relevant factors, which cannot be accommodated in a bounded formal framework. However, almost none of the potential complexities arise in any specific situation. Further, most of the ones which do arise turn out to be irrelevant to your purposes at the time, so you can ignore the variations they engender. You can easily see, or check, how the relevant factors play out. So the details of the actual situation you are in are generally adequate to resolve the difficulties that a general rational theory could not. You can access these details using perception and dialog.
- In context, it’s usually easy to resolve linguistic ambiguities (both syntactic and semantic) because you can figure out what someone is trying to say based on what they are trying to accomplish and which visible aspects of the concrete situation they must be talking about. When it’s not clear, you can ask.
- More-or-less truths can usually be resolved into “more” or “less” based on situational specifics. Whether or not a generalization applies is usually obvious.
- Uncertainty resolves into factual outcomes that you can usually deal with when they arise. You can figure out how to cross the river when you get there.
“Usually” is important here, of course. All these resolutions are error-prone. When reasonableness goes wrong, you may need to backtrack and clean up a mess. Sometimes it is better to plan ahead. Sometimes, mere reasonableness is inadequate, and it is better to apply systematic rationality! The point of this Part, though, is that most everyday activity, including much of the work of technical professionals, is handled reasonably, and that suffices. In Part Three, we’ll see how reasonableness is a necessary support for rationality as well.
The aim of Part Two is not to give a comprehensive account of reasonableness for its own sake. That would be fascinating, but out of scope for this book. Instead, we’ll concentrate on the features of reasonableness that contribute to its role in rationality and meta-rationality—which are what The Eggplant is about.
The structure of Part Two
Part Two begins with two chapters about the sort of explanation it offers, which might not be as you’d expect. The first chapter distinguishes it from cognitive science; The Eggplant is not a theory of mental processing. The second explains that Part Three does not cover quite the same subject matter as rationalism, which affects the sort of understanding Part Two offers.
The middle chapters of Part Two are obviously non-philosophical (unlike rationalism and cognitive science). They explain various aspects of reasonableness: its purposefulness; its public accountability; the powerful uninterestingness of routine activity; and the role of perception and of linguistic communication, particularly reference.
Then, two chapters reconsider the philosophical themes of ontology and epistemology in the light of our understanding of reasonableness.
The last chapter of Part Two, on instructed activity, serves as a bridge into Part Three.