Okay, the user wants me to translate "purely mechanical" into Japanese. Let me think about the correct term here. "Purely" can be translated as "純粋に" or "完全に", but in the context of mechanics, "純粋に" might be more appropriate. "Mechanical" is "機械的" in Japanese. So combining them, "純粋に機械的" would be the direct translation. However, I should check if there's a more natural phrase. Maybe "完全に機械的な" could also work, but the user specified to translate directly. Since the original is in English, I need to make sure it's not already in Japanese. The input is "purely mechanical", so it's not in Japanese. Therefore, the translation should be "純粋に機械的". I'll go with that.