QFT Book Quote: Looking for Source

[DarMM]

This seems like the best place to ask this.

There is a famous QFT textbook that contains a line like "in field theory one learns humility".

Does anybody happen to know what textbook this is?

 

[meopemuk]

Perhaps this one:

"The more one thinks about this situation, the more one is led to the conclusion that one should not insist on a detailed description of the system in time. From the physical point of view, this is not so surprising, because in contrast to non-relativistic quantum mechanics, the time behavior of a relativistic system with creation and annihilation of particles is unobservable. Essentially only scattering experiments are possible, therefore we retreat to scattering theory. One learns modesty in field theory."
G. Scharf, Finite quantum electrodynamics. The causal approach, (Springer, Berlin, 1995)

 

[DarMM]

Thanks! That was driving me mad!