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Dual-process theories of reasoning suggest that humans reason using two processes often referred to as process 1 (heuristic) and process 2 (analytic). When presented with a situation requiring any sort of reasoning or decision making, process 1 automatically engages and generates an initial mental model to address the situation. Process 2 may or may not be engaged to assess the initial model as a plausible solution. In a study by Kryjevskaia , a “screening” question regarding a pulse on a spring aimed to identify students with relevant content knowledge who nevertheless seemed to rely on process 1 when answering a subsequent “target” question. The study was offered as evidence that dual-process theories can explain some discrepancies in student responses to related questions. The study described here assesses the same pair of questions for their ability to distinguish between incorrect answers that stem from inadequate conceptual understanding and those that stem from reasoning approaches. We use Frederick’s cognitive reflection test as part of this analysis. Our results largely support a dual-process-theories perspective of student reasoning. Published by the American Physical Society2025
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This content will become publicly available on June 1, 2026
Evolution of complexity and the transition to biochemical life
While modern physics and biology satisfactorily explain the passage from the Big Bang to the formation of Earth and the first cells to present-day life, respectively, the origins of biochemical life still remain an open question. Since life, as we know it, requires extremely long genetic polymers, any answer to the question must explain how an evolving system of polymers of ever-increasing length could come about on a planet that otherwise consisted only of small molecular building blocks. In this work we show that, under realistic constraints, an abstract polymer model can exhibit dynamics such that attractors in the polymer population space with a higher average polymer length are also more probable. We generalize from the model and formalize the notions of and for chemical reaction networks with multiple attractors. The complexity of a species is defined as the minimum number of reactions needed to produce it from a set of building blocks, which in turn is used to define a measure of complexity for an attractor. A transition between attractors is considered to be a if the attractor with the higher probability also has a higher complexity. In an environment where only monomers are readily available, the attractor with a higher average polymer length is more complex. Thus, by this criterion, our abstract polymer model can exhibit progressive evolution for a range of thermodynamically plausible rate constants. We also formalize criteria for and evolution and explain the role of autocatalysis in obtaining them. Our work provides a basis for searching for prebiotically plausible scenarios in which long polymers can emerge and yield populations with even longer polymers. Additionally, the existence of features like history dependence and open endedness support the view that the path from chemistry to biology was one of gradual complexification rather than an instantaneous origin of life. Published by the American Physical Society2025
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- Award ID(s):
- 2218817
- PAR ID:
- 10598358
- Publisher / Repository:
- Physical Review Journals
- Date Published:
- Journal Name:
- Physical Review E
- Volume:
- 111
- Issue:
- 6
- ISSN:
- 2470-0045
- Page Range / eLocation ID:
- 064403
- Subject(s) / Keyword(s):
- Origins of life Autocatalysis Chemical reaction networks Thermodynamics Chemical complexity Evolution
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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