Mankind exhibit a great progress of like nature. Compared with brutes, the savage, higher in his self-maintaining conduct, is higher too in his race-maintaining conduct. A larger number of the wants of offspring are provided for; and parental care, enduring longer, extends to the disciplining of offspring in arts and habits which fit them for their conditions of existence. Conduct of this order, equally with conduct of the first order, we see becoming evolved in a still greater degree as we ascend from savage to civilized. The adjustments of acts to ends in the rearing of children become far more elaborate, alike in number of ends met, variety of means used, and efficiency of their adaptations; and the aid and oversight are continued throughout a much greater part of early life. In tracing up the evolution of conduct, so that we may frame a true conception of conduct in general, we have thus to recognize these two kinds as mutually dependent. Speaking generally, neither can evolve without evolution of the other; and the highest evolutions of the two must be reached simultaneously. § 6. To conclude, however, that on reaching a perfect adjustment of acts to ends subserving individual life and the rearing of offspring, the evolution of conduct becomes complete, is to conclude erroneously. Or rather, I should say, it is an error to suppose that either of these kinds of conduct can assume its highest form, without its highest form being assumed by a third kind of conduct yet to be named.