Text in Big5
Introductory Remarks -- What this section appears to me to be about:
不是而然 may mean that the individual propositions are denied, but that the implication is affirmed. See the fourth pair of Venn diagrams below. Or it may mean that the subset is held to be necessarily void when the superset is void, and so there is a concordance between the status of the superset and the status of the subset.
The Mohists deny that people can be fated to do ill or to have bad things happen to them that they are not themselves responsible for, e.g., an early death.
Consider the following cases:

(about to enter door {enter door}) (about to die early
{die})
(move all the way to the door {enter door}) (live a full life
{die})
(~maintain motion toward door {~enter door}) (~hold to mandate
{~keep mandate})
In the first pair, "entering the door" and "dying" may or
may not occur after
some progress is made toward those states. Interpretation
of the second pair
depends on what is implicit in the phrases "all the way" and
"full." In one
sense, if you have moved "all the way to the door" there is no
alternative to
plowing all the way through. In the third pair, prevention of
preparatory
action prevents the final result.
On Anti-fatalism
~approaching well --> ~falling in well. 不是而然
A F
~A --> ~F
1 1 1 paradigmatic: A=0,
F=0
1 0 1 countercase: A=0, F=1
0 1
0 "不是而不然" indicates that were
0 0
1 neither antecedent nor consequent
instanced then the implication
would be shown true.
{且夫讀書,非好書也。} (original text of next
line)
夫且讀書,非讀書也。好讀書,好書也。 (These 2 emended
lines
且鬥雞,非鬥雞也。好鬥雞,好雞也。 (were wrongly
changed.)
且入井,非入井也。止且入井,止入井也。
且出門,非出門也。止且出門,止出門也。
世相與共是之。
※若若是,且夭,非夭也。
壽,夭也。
有命,非命也。非執有命,非命也。
無難矣,此與彼同類。
世有彼而不自非也。
墨者有此而罪非之。
無也故焉,所謂內膠外閉<>而不解也。
此乃不是而然者也。
{Reading
a book is not liking a book.}
Being about to read a book is not to read a
book. Liking to read a book is
liking a book. {{Wrong. See my own emendation
below.}}
Being about to conduct a cock fight is not conducting a cock
fight. Liking a
cock fight is liking cocks. {{Wrong. See my own emendation
below.}}
Being about to fall into a well is not falling into a well.
Being stopped from falling into a well is to not fall in a
well.
Being about to go out the door is not going out the door.
Being
about to exit is not to exit. Being stopped from preparing to exit,
however, is
being stopped from exiting.
Everyone in the world affirms the preceding
propositions.
If the former propositions are correct, then it follows that
"early death" is
not early death, and only a ripe old age can be considered an
early death. ==
(Die only if lived a "full life".)
To have been given a
long [potential] life-span does not mean that you are fated
to live a long life.
If you do not maintain that mandate for a long life-span
(if you don't take
care of yourself in all ways), then you will in effect negate
your mandated long
life-span. There is no problem with this doctrine. The
latter propositions are
similar to the preceding ones. The people of the world
accept those cases and
do not condemn themselves/ hold themselves to be in
self-contradiction. The
Mohists hold the latter propositions, and are bitterly
opposed. There is no
other reason than that [the common people] are stuck on the
inside and locked up
on the outside and they can't get themselves freed up.
**The latter are cases
which [the general population] makes denials but where
things really are that
way.** (Cross out as an unsatisfactory translation.)
Argument appears to be that it is contradictory to hold the first several propositions and yet deny the second group of propositions.
In general, people see that preparation precedes putting something into operation. If they are right, then there is no such thing as "early death," i.e., a death without adequate preparation.
If there can be an "out of season" death, then events can be uncaused.
If one does not obey one's mandate, then one in effect negates that mandate. (The necessary preceding events are prevented, so the desired result is prevented.) That's analogous to the following:
If one does not carry through with one's approach to a well, then one cannot fall into the well. So the only way you can die is if you do everything you are "fated" to do before you die.
}}