Skill (lectical™) levels
- skill/lectical levels
- orders of hierarchical complexity
- order of abstraction
The names and numbers for the most commonly observed skill/lectical levels are shown in the table below, including the approximate ages and educational levels at which they generally become dominant.
| Level | Fischer name | Age of onset | Education |
| 0 | Single reflexive actions | Birth | n/a |
| 1 | Reflexive mappings | 6 wks | n/a |
| 2 | Reflexive systems | 3 mos | n/a |
| 3 | Single sensorimotor actions | 6 mos | n/a |
| 4 | Sensorimotor mappings | 10 mos | n/a |
| 5 | Sensorimotor systems | 15 mos | n/a |
| 6 | Single representations | 21 mos | n/a |
| 7 | Representational mappings | 4-5 yrs | 0-K |
| 8 | Representational systems | 7-8 yrs | 1-2 |
| 9 | Single abstractions | 10-11 yrs | 4-5 |
| 10 | Abstract mappings | 14-15 yrs | 8-9 |
| 11 | Abstract systems | 22+ years | 15-16 |
| 12 | Single principles | 26+ years | Ph.D.+ |
In texts, hierarchical complexity is reflected in two aspects of performance, the hierarchical order of abstraction of concepts and the logical organization of arguments. Hierarchical Complexity Theory predicts that some increases in hierarchical complexity will take the form of increasing hierarchical order of abstraction. This is because new concepts are formed at each complexity order as the operations of the previous complexity order are "summarized" into single constructs (Fischer, 1980). Burtis (1982) and Halford (1999) suggest that this summarizing or "chunking" makes more complex thought possible by reducing the number of elements that must be simultaneously coordinated, freeing up processing space and making it possible to produce an argument or conceptualization at a higher complexity order. For example, the concept of honor, which appears for the first time at the abstract mappings level, "summarizes" an argument coordinating concepts of reputation, trustworthiness, and kindness constructed at the single abstractions level. Similarly, the concept of personal integrity, which appears for the first time at the abstract systems level, summarizes an argument coordinating concepts of honor, personal responsibility, and personal values constructed at the abstract mappings level.
The figure below illustrates hierarchical integration.

(Complete references for the articles cited in this panel can be found under the references tab.)
Fischer defines 5 tiers, each of which is associated with a primary order of abstraction. These are reflexive actions, sensorimotor actions, representations, abstractions, and principles. Within each tier there are 3 complexity levels. This means there are 13 hierarchical orders of abstraction between single reflexive actions and single principles. These are associated with complexity levels as follows:
Hierarchical order of abstraction
| Level | Fischer name | Order of Abstraction | Logical structure |
| 0 | Single reflexive actions | 1st order actions | Definitional |
| 1 | Reflexive mappings | 2nd order actions | Linear |
| 2 | Reflexive systems | 3rd order actions | Multivariate |
| 3 | Single sensorimotor actions | 1st order schemes | Definitional |
| 4 | Sensorimotor mappings | 2nd order schemes | Linear |
| 5 | Sensorimotor systems | 3rd order schemes | Multivariate |
| 6 | Single representations | 1st order representations | Definitional |
| 7 | Representational mappings | 2nd order representations | Linear |
| 8 | Representational systems | 3rd order representations | Multivariate |
| 9 | Single abstractions | 1st order abstractions | Definitional |
| 10 | Abstract mappings | 2nd order abstractions | Linear |
| 11 | Abstract systems | 3rd order abstractions | Multivariate |
| 12 | Single principles | 1st order principles | Linear |
First order, 2nd order, and 3rd order concepts are associated with definitional, linear, and multivariate logical structures, respectively.
A definitional logical structure identifies the concept and describes it in terms of a single aspect. For example, at the single representations level (1st order representations), definitional logic allows representations to stand in for persons, objects, simple states, or simple actions—as in, “I not touch that.” At the representational mappings level (2nd order representations), a linear logical structure (referred to as a mapping by Fischer and his colleagues) describes the relationship between representations—as in, “If you're good, your mommy might buy you ice cream,” in which being “good” is coordinated with a particular concrete benefit. At the representational systems level (3rd order representations), the logical structure is multivariate. Multiple outcomes of behavior can be considered—as in, “If I am good, I won't get punished, and I might get to do something fun.” For simplified examples click here.
