The first chapter advises that as one begins to name names, or draw distinctions between various aspects of the Tao, one moves further away from that all-inclusive nature of oneness, the Tao.
Yet Chapter one also speaks to the internal and external qualities of the Tao and, thereby, introduces the student to both the existence, and the initial example, of dualistic natures.
In Chapter Two a common pitfall of dualities is exposed when one views but one aspect in isolation of its supposed opposite. While this principle is presented, in the main, in a somewhat cryptic manner, it is followed by a series of examples of what may be considered as commonly observable dualities.
Some following one pattern:
The mutual production of being and nonbeing
The mutual completion of difficult and easy
The mutual formation of long and short
The mutual filling of high and low
The mutual harmony of tone and voice
The mutual following of front and back
These are all constants.<1>
Or another:
Indeed the hidden and manifest give birth to each other
Difficult and easy compliment each other
Long and short exhibit each other
High and low set measure to each other
Voice and sound harmonize each other
Back and front follow each other<2>
and some with a more poetic addition than others.
Life and death, though stemming from each other,
seem to conflict as stages of change
Difficult and easy are stages of achievement
Long and short as measures of contrast
High and low as degrees of relations
But since the varying of tones give music to a voice
And what is is the was of shall be, <3>
To see that these couplets, as in the example of the Good and Not-Good, are mutually inter-dependent and co-arising is also to see that the seed of the one is to be found embedded within the body of the other.
The Ying-Yang symbol, attributed to Taoism, may be seen to provide an ever present visual reminder of this concept, where the inclusion of a small "spark," of opposite hue, may be likened to that seed.
References:
1> Robert G Henricks
Te-Tao Ching - Modern Library
2> John C.H. Wu
Tao Teh Ching - Shambhala Publications
3> Whitter Bynner
The Way of Life - Perigee/ Berkley Publishing Group