性行為的發展

正如已經解釋的那樣，每一個人必須採用的第一個性腳本是性別角色行為腳本，這個腳本規範他/她的“適當的”性別角色行為。從出生的那一刻起，女孩和男孩會獲得不同的性別特徵的名字。他們被有差異性地著裝和對待。隨著他們發育到孩童期，他們會得到不同的玩具並被告知“真正的女孩”和“真正的男孩”是什麼樣和如何作為。一旦他們進入青春期，他們的性別角色就已經內化到相當大的程度，而且他們的性欲期待（erotic expectation）和性欲行為會定型下來。毋庸置疑，同樣地，這兩個腳本的採用會先於任何可能的生殖腳本的採用。

由此可以斷定：要想在女性和男性的“性的”行為中區分出“自然差異”是脫離常規的。畢竟，性別角色行為既被腳本加以塑造，性欲行為也被腳本加以塑造了。此外，性別角色行為會先于性欲行為而習得，因此起初它就會發生改變。基於早前的兩個性腳本，隨後任何可能的生殖行為腳本就會被採用。簡而言之，指望在很大程度由社交學習所形成的性腳本裏找到“自然”的行為，是不合適的。無論如何，當探討人類的性行為的時候，要發現性行為在文化掩藏之下的生物基礎是十分困難的。

不過，我們確信性的生理方面，即個人的性能力、性動機和性行動，在人的一生中會經歷持續的改變過程。性腳本的採用過程在成年期也許或多或少就得以完成，但是，隨著歲月的流逝，性腳本通過行為所表現出來的方式也發生著改變。下面，我們將按照從嬰兒到老年的各個不同時期，簡要闡述這些改變過程。

Stages of Development

As already explained, the first sexual script human beings have to adopt is that which defines their “proper” gender role behavior. From the moment there are born, girls and boys are given different, gender-specific names. They are dressed differently and treated differently. As they grow into childhood, they are given different toys and are told what “real girls” and “real boys” are like and how they behave. Once they reach puberty, their gender roles have become internalized to a very great extent and shape their erotic expectations and behavior. Also, needless to say, the adoption of both of these scripts precedes any possible reproduction.
It follows that it is an error to look for “natural differences” in female and male “sexual” behavior. After all, both gender role behavior and erotic behavior are scripted. Moreover, gender role behavior is learned before erotic behavior and therefore colors it from the very beginning. The script for any possibly following reproductive behavior is then adopted on the basis of the two earlier scripts. In short, it is inappropriate to look for “nature” in what is largely the result of social learning. In any event, when it comes to human sexual behavior, it is extremely difficult to find the biological basis beneath its cultural superstructure.
Nevertheless, we know that the physical side of sex, i.e. a person’s sexual capacity, motivation, and performance, is subject to continuous changes throughout the life span. The adoption of sexual scripts may be more or less complete in adulthood, but the way in which they find expression in behavior also changes over the years. The following sections provide brief descriptions of these changes at various stages of life from infancy to old age.