Figure 1. The Power of an experiment is determined by the Effect Size. (Top) According to the ES and Variance in comparing young, old and old rejuvenated cohorts in our 2003-2020 studies we show that with these parameters N=4 justifies independence in our samples and larger N does not significantly improve on this justification. (Bottom) If hypothetical samples have high variance (and thus normalized effect size is reduced), then more samples (higher N) are needed to procure similar power in an experiment. Generally, an increase of sample size is needed for increasing the Power to discern less-tangible phenomena that are not statistically detectable without such N increase.