Conventional analog and digital electronics are based only on electric signal processing. The thermal state of a device may represent information too. At a nanometer scale, heat propagation can be extremely fast, which makes thermal computing an emerging field of research. Our proposed novel active device (phonon transistor = phonsistor) and thermal electric logic circuit (TELC) are made up of only bulk type intrinsic domains, consisting of significantly fewer regions and interfaces compared to standard complementer MOS (CMOS) based systems. The basis of TELC operation is the thermal or hot electron coupling between electron devices containing metal-insulator transition (MIT) material. The physical appearance and the operation of TELC are somewhat analogous with the neuron.