The substitution made by Moore seems to be taken as read. It is implemented implicitly, in silence, unnoticed by the author himself, who affirms a few lines later, that nothing can be substituted for good. However, this silence means many things. It is a suggestive silence. Its void is actually full of an entire philosophical tradition.

In these lines, a double disappearance of the concept of value can be noted.

Firstly, value disappears as there is an analytic identity between good and value. Value is nothing but a synonym for the word “good” and has no content by itself: it is an inconsistent concept, an empty shell. Value would maintain the dignity of a consistent concept if it were at least assigned a synthetic identity with good , but this is not the case here.

Secondly, above all, value, as a mere synonym, disappears as Moore continually repeats that nothing can be substituted for good (in direct contradiction with the substitution he has just made). If all we can say is that “Good is good”, then we are not allowed to say “Good is value”, even in a tautological sense.
In other words, the concept of value no longer has the “dignity” of a synonym, an empty shell. At present, value is not even a synonym anymore: it is a shadow, a word which disappears as soon as it is uttered, the equivalent in Moral Philosophy of a point in Mathematics, which has no length, width, or height, a kind of non-being.

Moore’s book is fascinating as it reveals this phenomenon in action in the history of moral philosophy: the disappearance of the concept of value in favour of that of good.

2) The confusion between good/value/worth/ought to/existence

Naturally, the section that we have just examined is not the only one in which this confusion may be found. In fact, Moore continues, despite his intention, to provide synonyms for the word “good”: Whenever he thinks of intrinsic value, or intrinsic worth, or says that a thing ought to exist, he has before his mind the unique object—the unique property of things—that I mean by good ¹.

At present, no less than four concepts have been analytically identified with the concept of good: "worth", "value", "ought to", "existence" (or, if we prefer, “ought to exist”). "Ought to" refers to a "duty" or "moral obligation".

Therefore, according to Moore, "to be good" is equivalent to:
- Having worth
- Having value
- Ought to exist, which means "to be a duty" or "to be a moral obligation".

These concepts, as synonyms for good, are synonymous for one another: they have the same meaning.

Nevertheless, maintaining that “having value” is equivalent to “ought to exist” not only involves making a confusion between two concepts, which are actually distinct, but also amounts to making the dogmatic judgment (an unfounded judgement) that only existing things are likely to have a value. To this idea, we can oppose the axiological judgment that only the ideal, dreams, or artificial heavens, (in short, all that does not exist) have value.

1. Ibid., chap.1, §13