2.6 Reflection enables the development of higher-order reasoning processes and therefore the development of metacognition or metathinking in adolescents.
2.8 Reflection aids the development of propositional reasoning ability in early adulthood and late adolescence.
2.9 Reflective processes are integral to higher-order reasoning processes applied during the solving of complex problems.
2.10 Axiomatisation and formalisation are guided by logic and purposeful thinking, are based on processes of reflective abstraction and are metacognitive, reflective processes.
See other related assertions on page 21 in the book The Taxonomy of Metacognition.