This paper draws on authors' recent works on cybernetics, complexity theory, quantum computing, Artificial Intelligence, deep learning, and algorithmic capitalism, and these ideas are brought together to develop a critical philosophy of the postdigital. Quantum computing is based on quantum mechanics and offers a radically different approach from classical comouting based on classical mechanics. Cybernetics, and complexity theory, provide insight into systems that are too complex to predict their future. Artificial Intelligence and deep learning are promising the final stage of automation which is not compatible with the welfare state based on full employment. We have thus arrived into the age of algorithmic capitalism, and its current phase, 'biologization of digital reason' is a distinct phenomenon that is at an early emergent form that springs from the application of digital reason to biology and the biologization of digital processes. Rejecting a fully mechanical universe, therefore, a critical pedagogy of the postdigital is closely related to Whitehead's process philosophy, which is a form of speculative metaphysics that privileges the event and processes over and above substance. A critical philosophy of the postdigital is dialectically interrelated with the theories such as cybernetics and complexity theory, and also processes such as quantum computing, complexity science, and deep learning. These processes constitute the emerging technoscience global system, perpetuate (algorithmic) capitalism, and offer an opportunity for techno-social change.