The analysis of well-known thermodynamic equations related to the crit
ical point and established before the formulation of the scale invaria
nce hypothesis reveals that the main results that follow from this hyp
othesis do not differ from those contained in the thermodynamic equati
ons mentioned above. Therefore, the scale invariance hypothesis does n
ot contain any novelty with respect to the critical point. It is point
ed out that the basic relationship between the critical indices, d nu
= 2 beta + gamma, which expresses analytically the scale invariance hy
pothesis, follows from the thermodynamic equations for the critical po
int established before this hypothesis, and, as a consequence, may be
extended to the phase transitions of the second kind. A new proof of t
he equality nu = (d - 1), where nu is the critical index for the surfa
ce tension, is also given.