"The signature of G-d is truth" (Sanhedrin 64a). "Accept the truth from wherever it comes" (Rambam, Introduction to Avot). There are few values more important than that of truth. While Jewish law allows and encourages one to tell a white lie for the sake of peace (Yevamot 65b), such has its limits.
"And G-d blessed them; and G-d said unto them: 'Be fruitful, and multiply, and replenish the earth, and subdue it; and have dominion over the fish of the sea, and over the fowl of the air, and over every beast that walks on the land'" (Breisheet 1:28). Here we have the source for the very first mitzvah of the Torah--or do we?