How does an extensive definition (or maximum possible analysis) of P differ from logical consequence of P.
Logic, as a performance of human beings, does not operate on "full definitions" or on Wittgensteinian "state of affairs". It operates on the form, or ostensive structure, of the argument.
a is F;
All y that are F are G;
Therefore, a is G.
This argument is valid even though there are no definitions provided for a, y, F and G, outside the type of argument that they are. And logic effectively stops once you are satisfied that the argument is valid.
Thus, logic does not require definitions.
Actual definitions will be required only when you apply logic. Application of logic is not logic.
Application of logic doesn't operate on the real things that may be referred to in arguments and formulas. It operates on the beliefs that you have about the world and beliefs can be very approximate models of the states of affair of the real world.
The notion of logical consequence does not require you to understand or know anything about the real world outside your head.
Application of logic, on the contrary, requires you to believe something about the real world to justify that you take the premises to be true.
Still no definitions required, though, and certainly no knowledge required of the "possibility of the state of affairs written into the thing itself".
All definitions have to stop somewhere. You can only analyse concepts up to the point where you can't go any further, always far short of the reality of the states of affair of the real world.
I don't believe that this has ever been a problem for the survival of homo sapiens. All humans do deductive inferences, routinely and without even being aware that they do. Homo sapiens already did that 200,000 years ago without obviously the possible benefit of Wittgenstein's counsel.
6.1251 : Hence there can never be surprises in logic.
What is true is that all that is possibly in the conclusion is already somehow in the premises, so there is nothing new in the conclusion.
However, to say that there is "no surprise in logic" is a very unfortunate expression.
Surprise is a mental state and we can definitely be very, very surprised upon discovering that a logical formula is valid.
Our ability to assess the validity of logical formulas using only the power of our own brain to do so is limited to very simple formulas and each formula is a special case. Many thinkers in history thought like Wittgenstein does in the extract provided, but they essentially talked from ignorance.
Even for simple arguments, what is new is the conclusion itself. Socrates being mortal follows from Socrates being a man and all men being mortal. Yet, it is effectively not written in the premises that Socrates is mortal.
The situation is very similar to that of arithmetic: 5 + 3 = 8 ... There is nothing new in the result 8 compared to the addition of 3 and 5. Yet, it is a fact that "8" does not appear at all in "3 + 5". So, what is new is the result of the operation 3 + 5. Isn't that something? Something new?