The teaching of one man or a compilation of the learning of many wise men, it is not all that clear.
Laotzu is an entity that has produced a cache of knowledge that has been handed down to us by Chinese scholars since the seventh century B.C. The info is organized into 81 sayings or verses. This entity that produced this knowledge is not fully known as a single man or an accumulation of scholars through many centuries. Laotzu however, is known to not like writing down knowledge. His or their belief is that the act of organizing the knowledge into written form has a negating effect on the knowing. The writing limits the info in such a way as to change it's importance as a positive factor in ones knowing. He was big on us knowing whats what by us using our own where withal. A favorite saying attributed to Laotzu is "A fish that is thirsty needs psychological help" Very enlightening to people who have it all but don't know it.
One reference used for this introduction to the Tao Teh Ching was "The Way Of Life according to Laotzu "
translated by Witter Bynner
The Way of Life, According to Laotzu