IV Maccabees 5:9

9 And you will be acting, I think, still more senselessly, if you follow vain conceits about the truth.

IV Maccabees 5:9 In-Context

7 For wherefore, since nature has conferred upon you the most excellent flesh of this animal, do you loathe it?
8 It seems senseless not to enjoy what is pleasant, yet not disgraceful; and from notions of sinfulness, to reject the boons of nature.
9 And you will be acting, I think, still more senselessly, if you follow vain conceits about the truth.
10 And you will, moreover, be despising me to your own punishment.
11 Will you not awake from your trifling philosophy? and give up the folly of your notions; and, regaining understanding worthy of your age, search into the truth of an expedient course?

The Brenton translation of the Septuagint is in the public domain.