This is a question for historical generalisation rather than for pure theory.

这是历史概括，而不是纯理论。

Psychology shifted away from pure theory and towards more careful and systematic empirical observation.

心理学从纯理论转向更仔和系统经验观察。

But all our talk was limited to pure theory and nothing else.

但是我们所有谈话都仅限于纯理论，没有别。

These purely theoretical concepts led the way to  atomic theory and the unfulfilled biology field.

这些纯理论概念引领了原子理论和未实现生物学领域。

But the pure theory of what determines the actual employment of the available resources has seldom been examined in great detail.

但是，很少详研究决定可用资源实际使用纯理论。