[1] “Constant” is meant as changeless and everlasting.
[2] I use the phrase “all things” for the more literal “the ten thousand creatures (things).”  Similarly in Chapters 2, 4, and many other Chapters such as 28 and 29, I use “the world” for “all under Heaven.”
[3]Wu-wei” does not mean doing nothing.  It means acting in a non-egoistic way, or without conscious purpose or agenda.  It refers to selfless action.
[4] The sage is being identified with Dao. Cf. Chapter 23 for more about this.  Instead of this line, earlier versions have:  The ten thousand things (all things) arise, but he does not begin them (start them, tell them [to do so]).
[5] “Lord” refers to Heaven which was thought to be the ruler of the universe.  The authors of this book do not actually believe there is any such ruler.
[6] It is said that Heaven and Earth and the Sage are not ren.  “Ren” means humane or compassionate.  One might say they all have an attitude of detachment or indifference, or are dispassionate.
[7] “Straw dogs were used for sacrifices in ancient China.  After they had been used, they were thrown away and there was no more sentiment attachment to them.” -  W. Chan
[8] “This refers to a vessel which is said to have been in the Temple of Chou (or Lu).  It stands in position when empty but overturns when full.” – D. C. Lau  In the oldest known version, lines 3-4 read:  When swift flowing waters gather against it, It cannot hold out very long.  “But what is the point of lines 3 and 4?  The answer might be provided in the following words of L. Kang (c. 196-264):  ‘When a tree stands above all the rest in the forest, the wind is sure to break it; and when a mound stands out from the shore, the fast flowing water is sure to overwhelm it.’” – R.G. Henricks
[9] “Man has two souls, the p’o which is the soul of the body and the hun which is the soul of the spirit.  After death the p’o descends into the earth while the hun ascends to heaven.” – D. C. Lau  “As generally understood, hun is the spirit of man’s vital force, expressed in man’s intelligence and power of breathing, whereas p’o is the spirit of men’s physical nature, expressed in bodily movement.” – W. Chan
[10] The first three lines constitute meditation instructions.  The fourth line may be related in that it suggests governing without knowing.  A newborn infant has no knowledge of the world, having not yet distinguished anything in his consciousness, not even knower from known, much less me and world.
[11] “All commentators agree that the belly refers to the central or fundamental things of life and the eyes refer to the superficial things of life.” – W. Chan
[12] In the oldest known version, lines 1, 3-6 read:
            Favor is disgrace, like bondage.
            Why is favor disgrace?
            Favor is degrading (puts you in a dependent or subordinate or inferior position).
            Getting it is bondage,
            Losing it is bondage.
[13] The Chinese for “continuous” is “sheng, sheng.”  It means going on and on like a piece of rope with no beginning or end, boundless.
[14] Meditation instructions
[15] Meditation instructions
[16] The Chinese character for humanity is “ren” and for righteousness is “yi.” “Yi” is sometimes translated as “justice.”  However, as in Plato’s writings, in this case “just” means right.  This “yi” is a different character from that of Chapters 10, 11, and 22, which is translated as “the One” or “unity” or “oneness.”
[17] “Father, son, elder brother, younger brother, husband, and wife.” – W. Chan
[18] When it says “abandon sageliness” it means something like don’t put on sagely airs.  There are several characters in Chinese that are pronounced zhi.  There is one which means learning and another which means knowing, perceiving or being acquainted with something.  Only the first refers to abstruse knowledge or scholarship.  I always translate the first character as “learning” (as in Chapters 3 and 18) and the second as “knowledge.”
[19] Literally:  Reveal the undyed silk, embrace the uncarved block (pu).
[20] Some would translate this as “Between ‘yes’ and ‘no’ (approval or disapproval) . . .”
[21] Meditation instruction
[22] Shadowy in the sense of being vague and indistinct.  See Chapter 14.
[23] Or indistinct or dim.
[24] “The word “ching” (essence) also means “intelligence.”  “Spirit” “life force” (vital force). – W. Chan
[25] Some commentators think “this” refers to the Dao.  Others, that it refers to everything that has gone before in the chapter.
[26] See footnote 61.  There is another character pronounced de which means gain or obtain.  It is found in many chapters including Chapters 31, 39, 42, and 56.
[27] The last line of Chapter 23 (which I have omitted) is the same as Chapter 17, line 5.
[28] In some versions Chapter 24 comes between Chapters 21 and 22.
[29] This line refers to the principle of yin and yang.  They probably first meant sunless and sunny, then female and male, and finally general terms for the fundamental and opposing forces or principles of nature. – D. C. Lau.  “Generally speaking, Yin stands for a constellation of such qualities as shade (‘on the north side of the hill’) darkness, cold, negativeness, weakness, femaleness, etc.; while Yang (‘on the south side of the hill’) denotes light, heat, strength, positiveness, maleness, etc.  The Yin-Yang experts regarded the interaction of these cognates as the explanation of all change in the universe.” – R. B. Blakney.  Yin is the cosmic passive force, Yang the active force. – W. Chan.  “In Zoroastrianism Darkness is essentially evil; the principle of Light, essentially good.  The fundamental concept of Yin and Yang is quite different.  They are two interdependent and complimentary facets of existence, and the aim of Yin-Yang philosophers was not the triumph of light, but the attainment in human life of perfect balance between the two principles.” – A. Waley.  They are the Active Pole and Passive Pole of Universal Existence.
[30] “Original simplicity” is literally: the state of virgin wood, the uncarved block, pu.  We could then say:  “When the uncarved block splinters . . .”  “P’u (also translated as ‘uncarved block’) is the most frequent metaphor in the Tao Te Ching for expressing the utter simplicity of the Way . . . The Old Chinese pronunciation of p’u was phluk.  This is almost certainly related to the English word ‘block,’ which probably derives from the Indo-European root bhelk (beam).” – Victor H. Mair
[31] Alternative: The sage uses these as leading officials.
[32] Nobody seems sure of the translation of these last three lines.  Interestingly, the word “qi” which I have translated as “implements” occurs in many places in the book, but in this chapter, Chapter 41, and Chapter 67,  the lines in which it occurs seem terribly difficult to translate.  “Leading official” and “chief minister” (Chapter 67) are literally: Lord of the implements.  The last line contains the quotation of a saying. It involves a play on the word “zhi” which can mean to carve or to rule.  For this reason some translations have “the great ruler” instead of “the great carver.”
[33] Literally: what is under heaven.  The same is true of “world” in Chapter 29.
[34] “Symbolic of good omens.” – W. Chan
[35] “Symbolic of evil omens.” – W. Chan
[36] See Chapter 1.
[37] Literally: Though it is an uncarved block . . .
[38] Literally: Once the block is carved there will be names.  Names, in a sense, carve up the world conceptually and artificially.  We think that if we have a name for something we understand it fully, and that it is entirely different from things with other names.  But the world is messy, not clear-cut.
[39] Or: All creatures (the ten thousand things) entrust their lives to It, yet It does not act as their master.
[40] See Chapter 27.
[41] According to one version:  The Dao endures without a name.
[42] See Chapter 32.
[43] Literally: that nameless virgin (or uncarved) block.
[44] Two ways to try to achieve peace:  chasing desires vs. eliminating desires
[45] He does not practice wu-wei or non-ego motivated action.  He acts with an agenda, plotting and scheming.
[46] An expert at rites, rituals, and ceremonies, as well as etiquette.
[47] This refers back to the first four lines.
[48] Or “steady.”
[49] Or “become upright and firm (secure).”
[50] According to another text, this line should read, “A carriage is more than the sum of its parts.”  This makes no sense in the context of the second stanza.  Other translations in line with the present one are: “Hence the highest renown is without renown,” and “Too many carriages are like no carriages.”
[51] In some versions Chapter 40 comes between Chapters 41 and 42.
[52] I agree with Lin Yutang in making this chapter the first of Part II, instead of Chapter 38 as is usually done.
[53] The vulgar, students of the lowest type.
[54] It would have been better to say:  The great splash makes no ripples, but see Chapter 14.
[55] “It is often understood that the One is the original material force or the Great Ultimate, the two are yin and yang, the three are their blending with the original material force, and the ten thousand things are things carrying the yin and embracing yang.  The similarity of this process to that of the Book of Changes, in which the Great Ultimate produces the Two Forces (yin and yang) and then the myriad things, is amazing.  The important point, however, is not the specific similarities, but the evolution from the simple to the complex.  This theory is common to nearly all Chinese philosophical schools.  It should be clearly noted that the evolution here as in the Book of Changes, is natural.  Production (sheng) is not personal creation or purposeful origination but natural causation.” – W. Chan.  Yin and yang are also referred to as two breaths or forces generative of life.
[56] This is a different character from the yi of Chapter 19, etc. which is pronounced the same way.  It appears in Chapters 42, 43, 48, and 55.  It means:  increase, more, gain, benefit.
[57] Or, has no personal opinions or views.
[58] These last two lines can be translated:
             Ordinary people fix their eyes and ears on him,
            And he treats them all as his children.
[59] Three out of ten are still growing, three out of ten have begun to deteriorate, and three are in between.  As in the answer to the famous question of the sphinx, first we walk on four limbs, then on two limbs, and then on three (including a cane).
[60] The thirteen are the four limbs and nine apertures of the body.
[61] “The relationship between Tao and te is not clearly stated, but it seems clear the te follows Tao (Ch. 23) and that, while Tao produces all things, it is te that fosters them.  Furthermore, in ancient Chinese classics, te (virtue or characteristic) is often equated with te (to obtain).  It is generally understood that while Tao is what each thing has obtained from Tao.  In this sense, te is its virtue or characteristic.  When Ho-Shang Kung equated te with ‘one’ in his commentary, he probably had this in mind.” – W. Chan
[62] Alternative translation: but not make them dependent (or coddle them). The same line appears in Chapters 2, 10, and 77.
[63] See Chapter 10
[64] As in Chapter 25, I used the word “world” for the more literal “all things under heaven.”
[65] See Chapter 16 and Chapter 50.
[66] The openings are the sense organs and the doors are the doors of the mind.  Meditation instructions.
[67] “Forty-two texts, including the Fu I text, listed by Chiang His-ch’ang, have hsi (to follow) instead of hsi (to practice), but the two words were interchangeable.” – W. Chan   “Ming” and “guang” both literally mean light, although the latter is considered a bright light.  It seems we are supposed to use the light of the Dao to reach illumination or enlightenment.
[68] This chapter is all about how people make life into a struggle.  Note how the message here contrasts with the Christian idea, “narrow is the road.”
[69] In the Dao
[70] By the Dao
[71] Or, through the eyes of the person, or, form the viewpoint of the person.
[72] By knowing myself or what is within me.
[73] See Chapter 30.
[74] According to the earliest known version: One who knows It does not talk about It, One who talks about It does not know It.
[75] The point of these lines is that the sage is honest without condemning others.
[76] To the Dao.  See Chapter 55.
[77] “This sentence is not clear and commentators and translators have interpreted it in their own way.” – W. Chan. 
[78] “ . . . The most highly honored place in the house, where family worship was carried out, grains and treasures were stored, etc.” – W. Chan
[79] This line has been translated in various other ways.  Perhaps it ties in with the next to last line.
[80] Grant tutor, grand preceptor, and grand protector. – W. Chan
[81] See Chapter 56.
[82] The word translated as “virtue” (good deeds) is “de” – the same word as the one which refers to the Power of Dao. 
[83] See Chapter 34 which contains almost identical wording.
[84] “A li is about a third of a mile.” – W. Chan    Alternate translation:  A height of 800 feet.
[85] See Chapter 29.
[86] See Chapter 25, last line.  In my opinion, the idea of this line is related to the idea expressed in the next to the last line of Chapter 65.  The phrase translated as “on its own nature” in Chapter 25 is literally “the self-so,” and the phrase translated as “in their natural state” in Chapter 64 is literally “their self-so.”  The phrase is “zi ran” which can also mean as it is or own nature or such as it is.
[87] “The doctrine of making people ignorant has been criticized more than any other doctrine taught by Lao Tzu.  However, one must remember that his whole philosophy is against cunning, deliberation, and overdevelopment of knowledge.  Moreover, the Taoist sage himself is expected to be ignorant.  Perhaps he means the same thing as the ancient poet who sang:
            Without awareness or knowledge
            Follow the principle of the Lord.
The outstanding Neo-Confucianist, Chang Tsai, says, ‘If one does so (follows the principle of the Lord) deliberately or consciously one will lose the principle of Nature.’  But too many rulers in Chinese history have adopted the policy of keeping the people ignorant, and, rightly or wrongly, critics have held Lao Tzu responsible.” – W. Chan  In defense of the writers of this book I would say that they were afraid that learning would lead to cleverness and craftiness which in turn would be used for bad purposes.  The character “yu” turns up in Chapters 20 and 38 where it means foolish.  It also means simple.
[88] See Chapter 16.  See also the end of Chapter 64.
[89] See the beginning of Chapter 61 and Chapter 62.  An alternate reading:  Then the great congruence (compliance) [with the Dao] is attained.
[90] See Chapter 22.
[91] A number of translators use the word “compassion” rather than the phrase “deep love.”
[92] See Note 32 to Chapter 28. Literally “implement” (“qi”) rather than “chief minister.”
[93] Scholars are not sure about the meaning of the word translated “grieves.”  Other possibilities are: “yields” and “has deep love (compassion).”  But noting Chapter 31, “grieves” or “sorrows” is the best choice.
[94] “Rich people, in times of tumult, dressed up as peasants and hid their jade treasures under their clothes.” – A. Waley.
[95] Alternate translation: To know without thinking you know is best.
[96] Alternate version:  bu zhi, bu zhi – Not to know you don’t know is a disease.
[97] In the sense of caring for himself.
[98] See Chapter 50.
[99] And hence becomes a debtor.
[100] In some versions, Chapters 80 and 81 are placed between Chapters 66 and 67.