what is omitted in "what is"

[chance22]

I came across a sentence -- It is fatally easy, as one grows older, to slip into the habit of grumbling that nothing is what it was and lamenting the inferiority of what is.
I wonder what is omitted in this expression. Should there be "it", that is, what it is, or should I interprete it as what is what it was?
Thank you

[billmcd]

I came across a sentence -- It is fatally easy, as one grows older, to slip into the habit of grumbling that nothing is what it was and lamenting the inferiority of what is.
I wonder what is omitted in this expression. Should there be "it", that is, what it is, or should I interprete it as what is what it was?
Thank you

"what is" in this context = what exists. "It" is not necessary in this reference.

[emsr2d2]

What was and what is are two different things = The way things were and the way things are now are very different.

[chance22]

Thank billmcd and emsr2d2 for the explanation. Now I got the meaning of the sentence, but I think maybe grammatically, "what is" means "something that is" , it seems incompete. Usually I find expressions in this pattern:"what is here", "what it is". Can I say this sentence falls into one of these patterns but with certain words omitted, or "what is" can be used independently meaning "what exists now"?

[TheParser]

[QUOTE=chance22;833311]I think maybe grammatically, "what is" means "something that is"

NOT A TEACHER


(1) While we wait for the teachers' answers, may I congratulate you on your sense of

"what."

(2) According to my books, "what" is, as you suggested, sometimes a relative pronoun that means something like that which.

(i) I do not like what you said. = I do not like that which you said.

(ii) What you said is nonsense. = That which you said is nonsense.