王夫之易学中的实有思想与清初务实学风

王夫之治《易》，务实求真，主张非无而有，非虚而实．非妄而真，其批判矛头直指佛老，提出了天地自然皆为实有的思想，从客观实际出发，说明天地自然的本性。王夫之易学中的实有思想与清初务实学风有关，受着明清之际反对虚理，崇尚务实思潮的影响。从哲理或思辨意义上说，他对实有思想研讨之湛深，创获之丰富．超拔于同时代人。     

An effective metacognitive strategy: learning by doing and explaining with a computer‐based Cognitive Tutor

Recent studies have shown that self‐explanation is an effective metacognitive strategy, but how can it be leveraged to improve students' learning in actual classrooms? How do instructional treatments that emphasizes self‐explanation affect students' learning, as compared to other instructional treatments? We investigated whether self‐explanation can be scaffolded effectively in a classroom environment using a Cognitive Tutor, which is intelligent instructional software that supports guided learning by doing. In two classroom experiments, we found that students who explained their steps during problem‐solving practice with a Cognitive Tutor learned with greater understanding compared to students who did not explain steps. The explainers better explained their solutions steps and were more successful on transfer problems. We interpret these results as follows: By engaging in explanation, students acquired better‐integrated visual and verbal declarative knowledge and acquired less shallow procedural knowledge. The research demonstrates that the benefits of self‐explanation can be achieved in a relatively simple computer‐based approach that scales well for classroom use.