Vygotsky chose consciousness as a foundation for his approach to psychology, although it took several iterations to arrive at his final conception of a dynamic, semantic system, which included not only thought and language, the subject of most of his work up to that point, but how we refract our experience of the world through personhood as well. However, he had simply run out of time, and it is likely that his thinking on the matter would have evolved, although what he accomplished is of value not only on its own terms, but as key to understanding his work as a whole. Today the neuroscientific approach to consciousness has resulted in numerous theories, experimental work, and other forms of investigation, and interestingly, the two most prominent theories at this time address the two areas of most concern to Vygotsky: functional and phenomenal consciousness.