If I have seen further it is by standing on the shoulders of giants.
To quote Hillel Levine
Rationalism and empiricism usurp the authority of traditional knowledge—this authority being based on the consensus that tradition preserves an accurate record of some past revelation.... The epistemological dimensions of this conflict between evolution and
emanation can be traced through the frequent citation of the aphorism, "Dwarfs on the Shoulders of Giants," giving visual representation to the conflict. In its ambiguity, the aphorism seeks to reconcile conceptions of cumulative knowledge and the progressive model of time with conceptions of knowledge based on the authority of tradition and the degenerative model of time. While affirming the superior capacity of the ancient giants and the
authoritativeness of their literary legacy, it allows for the discrepant truth claims and discoveries of the contemporary dwarfs by emphasizing their indebtedness to predecessors.
Thus a rationalist can resolve the authority of the past with the new ideas of the present using the concept of standing on the shoulders of those who came before. Every new idea is only possible because of the groundwork laid by earlier generations.
The concept is refered to by Rav Yaakov of Lisa in his introduction to Chavot Daat. He does not attribute it, but writes:
If you fine an attack on one of the [earlier] poskim, do not think that my intention is to attack. Because I know that compared to the earlier authors I am as like nothing. It is like the analogy that has been made, 'like a dwarf riding on a giant.' However the analogy is not clearly understood, because our eyesight is so weak that we are like chicks who have not yet opened their eyes. Someone who cannot see well thinks that things are the opposite of teh turth, and cannot see properly even when he is raised up high.
However Isaac Newton was not the first to coin this phrase. It appears in the introduction to Shibbolei HaLeket which predates Newton by 400 years! And he is saying it in the name of his teacher, Rav Yishaya di-Trani who lived from 1180-1250.
Yet the truth is that Rav Yishaya (who is more commonly known as Tosefot Rid) was not the first to coin the phrase. He attributes it to the non-Jewish scholars.
Like the great prince, Rav Yishaya of Trani zt"l answered someone when he asked him 'how can a person have the audacity to challenge the words of the earlier Gaonim?, whose minds are as open as the doorway of a hall?' He answered with an aphorism that he heard from the non Jewish scholars. When the philosophers asked the greatest of them and asked 'Do we not admit that the earlier generations were wiser and smarter than us? Yet we speak against them and challenge their words in many places, and the truth is with us. How can this be?' The philosopher answered by saying 'Who sees further? The dwarf or the giant? Surely the giant because his eyes are much higher than the eyes of the dwarf. But if the dwarf sits on the neck of the giant - then who sees further? Surely the dwarf, because now his eyes are higher than the eyes of the giant. Simiarly, we are dwarves riding on the neck of giants because we see their wisdom and delve deeper, and we learn from thier wisdom to discover everything that we say. Not because we are greater than they were.
Who is the philosopher who Tosefot Rid refers to? It turns out that the earliest use of the phrase 'dwarfs on the shoulders of giants' is from Bernard of Chartres, quoted by John of Salisbury.
So it turns out that the phrase which is used to justify the modern innovations in Jewish thought by connecting it to the earlier generations is itself borrowed from a non-Jewish source and has no connetion to Judaism or the earlier sources.
Apparently there is a whole book on the phrase "On the Shoulders of Giants." I have only seen the few pages available on google book view:
(Of course there is a different but similar concept in Chulin 7a which explains how there is any room for later generations to come up with new halachot. The phrase of the gemara is "my ancestors left me a place to define myself." This allows for novella, but does not connect them to the views of the earlier generations).