It may be argued that the idea of such perfectability through knowledge is overstated and that it was not really something that 'stuck' after the 1700s and 1800s period itself. But here is a quote, one of many on the subject of science triumphing over faith from the famous French novelist and political agitator (dreamer?), Emile Zola:
Was it indeed true that the cultured young were still and ever in their silent forge, renouncing no hope, relinquishing no conquest, but in full freedom of mind forging the truth and justice of to-morrow with the invincible hammers of observation and experiment? (The Three Cities Trilogy: Paris, Vol 2)And later, Zola says, referring to the priest who has lost his faith,
And now the young men of intellect of whom he had despaired, that generation of the morrow which he had thought spoilt, relapsing into ancient error and rottenness, had appeared to him full of virile promise, resolved to prosecute the work of those who had gone before, and effect, by the aid of Science only, the conquest of absolute truth and absolute justice.We have many criticisms of the life sciences, not so much because we haven't solved all the problems in biology but for the amount of largesse and the braggadocio and self-aggrandizement that is involved. The same kind of boastful self-promotion is going on in the social sciences, especially as social scientists rush to do genomics--explaining all about your behavior and society in terms of genes. This awful abandonment of social science in favor of genetics is a clear confession of failure but not an acceptance that loss of funding should go with it--until and unless social sciences begin to live up to what we should expect of them: to understand behavior and society so as to improve it and the world we live in.
Societies are perhaps the ultimate 'emergent' phenomenon, not predictable from measurement on individuals any more than the pressure of a gas can be predicted by enumerating each of its molecules. It's a major challenge. We can easily imagine an improved society, but we don't yet know how to engineer or even to predict it.
Zola's comments show that for quite a while there was a belief that science would do this. The implicit promise of those still feeding at the NIH and NSF funding trough shows that the belief, or at least the rationale, persists. Isn't it time for some results?