A recent article commemorated C.N. Yang's great discovery of the Yang-Mills gauge theory. However, a netizen named c_y_lo vehemently fired back. C_y_lo, who normally assaults Einstein's General Theory of Relativity on some Chinese message board, declares that C.N. Yang is "at most a foot note[sic]" in the history of sciences and the Yang-Mills theory is simply wrong. Foaming at his mouth, c_y_Lo writes：“Pauli ... criticized this gauge theory as useless because of no mass is involved with Fermions.”

Apparently, c_y_lo did not understand Pauli's critical question posed to Yang. The question was not concerning the masses of the fermions, but those of the gauge bosons. Anyone with rudimentary education in physics can see that the Lagrangian in Yang's paper consists of a Dirac field with mass m and the gauage field B. See, Yang's paper, at http://www.thphys.uni-heidelberg.de/~maniatis/LectureAdv/yang-mills.pdf

Thus, Yang-Mills is a theory of massive fermions. This is plainly obvious, because Yang and Mills were looking at the isospin symmetry of proton-neutron at the time. Pauli's question to Yang was: "What is the mass of this field B?" [Ref：Gauge theory: Historical origins and some modern developments; Lochlainn O’Raifeartaigh, Norbert Straumann Journal: Reviews of Modern Physics - REV MOD PHYS , vol. 72, no. 1, pp. 1-23, 2000] Pauli was asking about mass or the absence of it of the bosonic force field B, not the mass m of the fermion field.

When Yang first presented the Yang-Mills theory to a group of physicists, including Pauli, the latter repeatedly asked Yang the same question, and Yang had to stop the presentation at one point. Many years later, C. N. Yang posed a hypothetical: "What if Pauli lived till the 1960s or 1970s?" Since then, the Yang-Mills theory has become the foundation of modern physics and is still an active area of research. Gauge invariance is now the fundamental principle underlying the Standard Model.

That old episode with Pauli proved the true genius of Yang. There is little dispute that Yang's contribution to human understanding of nature is at a fundamental level unsurpassed by anyone. It is natural that lesser minds could not and cannot understand the greater ones.

Quantum Chromodynamics ("QCD") is a straight application of Yang-Mills SU(3)_c gauge theory. QCD is an exact Yang-Mills theory with massless gluons as the gauge bosons. Despite this common knowledge, c_y_lo states: "Since gluon interacts with Quarks which have masses. Therefore, gauge symmetry must be broken, and this is verified by experiments. The 2008 Nobel Prized[sic] for Physics is given to such verification."

C_y_lo's misguided statement shows his cluelessness. There is no flavor gauge symmetry. The QCD gauge symmetry is in the color space of each quark flavor. The 2008 Nobel Prize was awarded for the discovery of a new quark flavor, which has to do with weak interactions. In other words, c_y_lo could not even understand what the Nobel Prize was about.

Pseudo-scientists(*) like C-y-Lo are usually harmless, as society rarely pays any attention to their frivolous ideas. Nevertheless, with the advent of the internet, many gullible people on the web may be attracted to such fakers, and their unfounded attacks on established sciences may weaken the foundation of our civilization.

In view of the new situation, once the C-y-Lo types crossed their line and meddle with true sciences, they must be exposed and discredited, so as to maintain the dignity and reputation of the sciences on the internet and beyond.

*The Chinese for such people is "minke".