Pattern Structure

• The patterns derive from our Conceptual Models. A pattern is a rule that describes what to do to generate the entity which it defines.

• Each pattern is a morphological law which establishes a set of relationships in space. It can be expressed as

  Read as “within context of types , the parts , are related by relationship .

  • Each law or pattern is itself a pattern of relationships with other laws.

• Each pattern is a three-part rule which expresses a relation between a context, a problem and a solution.

• Patterns exist within contexts — they are required to address certain needs. As such, patterns form a language. In it — [^pattern_langauge]

  • The elements are patterns
  • Each pattern has some structure that describes it as a pattern of smaller patterns — how they are created with respect to patterns.
  • Each pattern is also a rule.
  • The patterns are generative in nature — it tells us how to construct arrangements which satisfy the rules .
  • Patterns exist in various scales.

• The inner structure of the pattern can be understood by asking

  • ”What” precisely is present in the pattern. What is the context .
  • ”Why” does the pattern exist. What problem does it solve. What system of forces are involved in the pattern
  • ”When / Where” will this pattern work. We must define the exact range of contexts where the problem occurs and where the solution is appropriate.

• Because it is contextual, every pattern is self-contained. To say a pattern is alive is to say that there is an empirical relationship between a limited context, a set of forces and a pattern which resolves these forces.

• Every pattern within the pattern language is an operator which differentiates space — it creates distinctions where no distinction was before. This operator is concrete.

  • It is specific in that it gives rise to that particular pattern
  • It is general in the sense that it is specific to a general context which gives rise to the pattern.
  • The pattern language allows us to sequence these patterns together to create the final structure.

Working with Patterns §

• Discovering patterns begins with observation

  • Begin with a set of structures and study what common features they have (a hypothesized pattern)
  • Identify the problem that exists in those structures which lack the pattern — typically this requires us to identify the forces at work and how the pattern resolves these forces.
  • Knowledge of the invariants that come from domain knowledge then helps solve the problem. Patterns help us discover invariants.
  • Update our beliefs about the pattern by observing the structures again with the invariants in mind. In particular, we test if the pattern is good — if it satisfies these two criteria
    • The problem is real - The problem does occur within the context.
    • The configuration / pattern solves the problem - The pattern can resolve the problem without any side effects.

• One challenge is that — it is hard to be precise when it comes to patterns because there could be more than one formulation to the pattern. It helps, therefore, to think of patterns as fluid templates that capture some invariant in relation to some problem within some context.

• And once we have discovered the pattern, we must then identify how to reify it in the real world.

  • We must be able to sketch it
  • We must Name it so that we can talk about it further.

• Patterns are never final. They are subject to change given new evidence.

• Caveat: Even if a pattern seems sensible and has clear reasoning behind it, does not mean that the pattern is capable of generating life.

  • A pattern only works when it deals with all the forces present in the situation. However, in practice, it is difficult to know exactly what the forces in a situation are.
  • To assess whether a pattern can generate life requires relying on “feel” than intellect.
    • Patterns made from thoughts without feeling lack empirical reality entirely
    • Using “feelings” means that we are able to look at the totality of the system, and in this sense, it gives us a way to test the pattern — A pattern is likely good if and only if it makes us feel good
    • This ”feeling” is not tied to opinion, taste or notions.
      • It is hard to give up preconceptions of what things ought to be and recognize things as they are
      • Preconceptions and Opinions on what ought to be blind us from what is “real”. It stunts creativity
      • A pattern which is real makes no value judgments about the legitimacy of the forces in the situation. In this sense of unethical-ness, the pattern allows things to be alive.
    • In this context, feelings tie to a sense of empathy.
    • It is painstaking because it demands paying attention to these feelings
    • From an empirical perspective, this ties to using qualitative methods on top of quantitative methods.
    • At its core, this method relies on testing for the presence of The Nameless Quality. We feel the system-ness of the system.

• Patterns have a recursive structure — they exist within patterns and they contain patterns .

  • Pattern that exists within a larger pattern language is anchored and reinforced by the other patterns within that language.
  • Patterns must not consist of too many smaller patterns. It is harder to reify patterns that are too complex.

Links §

• The Timeless Way of Building by Christopher Alexander - Ch. 14, 15, 16, 17