SECTION I

墨子，小取，夫辯者，將以明是非之分… 

Now disputation is for the sake of making clear distinction between what is and what is not.

審治亂之紀，明同異之處，察名實之理，處利害，決嫌疑，焉摹略萬物之然，論求群言之比。
It examines the reasons for there being order or disorder, it makes clear where things are the same and where they are different, it makes investigations into the correspondences that exist between names and realities. weighs assets against liabilities or benefits against injuries, and resolves uncertainties. and in so doing it searches out the truth about the myriad creatures and seeks through analysis to compare the multitudes of discourses.

以名舉實，以辭抒意，以說出故，以類取，以類予。
One uses names to lift realities [up to our minds for examination], and uses reasoned discourse to express one's ideas. One uses persuasive discourse to put forth idea of causation (motivation). One accepts things for examination by their general natures and puts them forward [for examination by others] in the same way.

有諸己不非諸人，無諸己不求諸人。
Do not condemn in others what you find in yourself, and do not demand of other what you yourself do not have.

無諸己不求諸人。有諸己不非諸人，無諸己不求諸人。
Do not condemn in others what you find in yourself, and do not demand of others what you yourself do not have.

或也者不盡也。假者今不然也。
When something is qualified with the word "perhaps," it is because of the lack of exhaustive evidence for it. When something is qualified with the word "supposing," it is because at present that state of affairs does not exist.


效者為之法也，所效者所以為之法也。故中效則是也，不中效則非也，此效也。
 "Semblance" is the name for a law or rule for doing something. The thing of which a semblance is made is the standard by reason of which something is done.  So if a semblance hits the bull's eye, then it is correct. If it does not hit the bull's eye, then it is wrong. This is what is meant by a [good] semblance.

Paraphrase: A mapping or model is made to correspond to a deeper characteristic of nature. So what we are ultimately trying to do is to connect the mapping or model with the deeper characteristic of nature. Therefore when we make a mapping that is on target, then it is correct; when we make a mapping that is not on target, then it is incorrect.
 

{{Based on this passage, I think by shì and fēi Mo Zi means "what is really the case and what is not the case." So these terms should apply to individual propositions. Rán and bù rán, on the other hand, apply to compound sentences formed by the use of logical terms such as "if... then...." }}

其然也，有所以然也，其然也同，其所以然不必同。

The ways things are have their reasons. The way things are may be the same without the reasons for their being that way also being the same.

{{"Rán" here means "the way things are." The sentence says that there is a reason for any thing being the way it is, however, while two things may be or look the same, the reasons that they are the way they are need not be the same. [[For instance, two people are dead. One died of a real heart attack, but one died from a poison delivered by a clever assassin.]]}}
夫物或乃是而然，或是而不然，或不是而然。

Now things are such that people make statements about things that do happen and the implications they postulate on that basis are held to be valid, or people make statements about things that do happen but the implications they postulate on that basis are  held not to be valid, or the statements they use involve cases that do not occur and the implications they make about them are held to be valid.

    •Commentary: Examples of these three classes, shì ér rán, shì ér bù rán, and bú shì er rán, are:

    shì ér rán:  "If the north pole is cold, then food left outside at night will freeze."  Ordinary people will accept this statement.

    shì ér bù rán: "If Al Capone was a gangster, then Al Capone was human." Ordinary people will not accept this statement. (They may believe that killing is bad but execution is o.k.)

    bú shì er rán: "If you do not complete your education all the way through medical school, then you will not become a physician." Ordinary people will accept this statement.

things actually are that way, or people deny statements about them and actually they are that way, or people affirm such propositions yet they are not that way.