Talk only when spoken you... Children should be seen and not heard And yet... Research is showing us that only should children be encouraged to talk back but they need the exercise in practice to build crucial critical thinking skills for their lives. Critical thinking requires us not to passively accept everything we read, hear and see but rather to question, evaluate and make judgments. So how can parents teach critical thinking at home? Heidi Matisonn is a senior lecturer in bioethics at The EthicsLab, Department of Medicine, Faculty of Health Sciences at the University of Cape Town.