Religious views on truth
There is no unilateral agreement among the different denominations of Judaism concerning truth. In Orthodox Judaism, truth is the revealed word of God, as found in the Hebrew Bible, and to a lesser extent, in the words of the sages of the Talmud. For Hasidic Jews truth is also found in the pronouncements of their rebbe, or spiritual leader, who is believed to possess divine inspiration. Kotzk, a Polish Hasidic sect, was known for their obsession with truth.
Haskalah
The spreading of Haskalah affected Judaism as a religion because of how much the different sects desired to be integrated, and in turn, integrate their religious traditions. The effects of the Enlightenment were already present in Jewish religious music and opinion on traditionalism versus modernization. Groups of Reform Jews such as the Society of the Friends of Reform and the Association for the Reform of Judaism were formed because they wanted and actively advocated for a change in Jewish tradition, mainly rituals like circumcision. 
Another non-Orthodox group was the Conservative Jews, who emphasized the importance of traditions but viewed with a historical perspective. The Orthodox Jews were actively against these reformers because they viewed changing Jewish tradition was an insult to God and that fulfillment in life could be found in serving God and keeping his commandments. The effect of Haskalah was that it gave a voice to plurality of views, while the orthodoxy stubbornly preserved the tradition, even to the point of insisting on dividing between sects.