Modern machine learning systems excel at data driven optimization but remain confined by training objectives and input distributions. Conventional paradigms such as supervised, unsupervised, reinforcement, and self supervised learning operate within explicit boundaries defined by task specific loss functions and curated data. In biological systems, dreaming provides essential functions such as memory consolidation, emotional regulation, and creative recombination. Inspired by this, we propose Dreaming Machine Learning, a speculative framework in which models alternate between a wake phase of conventional training and a dream phase of unconstrained exploration. During dream states, networks may replay and recombine latent embeddings, pursue alternative objectives such as novelty or entropy maximization, or generate counterfactual and hallucinatory samples that extend beyond training distributions. These internal explorations enable the discovery of latent structures, novel hypotheses, and emergent patterns that are not accessible through standard learning. We outline potential applications of Dreaming Machine Learning in scientific discovery, creativity, anomaly detection, robotics, and personalized artificial intelligence, while highlighting open challenges of evaluation, stability, ethics, and sustainability. By formalizing a wake and dream cycle, Dreaming Machine Learning aims to expand artificial intelligence beyond pattern recognition toward imagination and hypothesis generation. The future of machine intelligence may depend not only on learning by doing, but also on learning by dreaming.